
Class _JEi&0 

Book ..1 }$% ^^ 

CoEyriglitN" 



CORfRIGHT DEPOSrC 



MODERN 

AIR-BRAKE PRACTICE 

ITS USE AND ABUSE 



A Book of Instruction on the Automatic 
and Straight Air Brake 

Together iv'ith ^estions and Ansnvers Covering a Complete Air Brake 
Examination for Enginemen, Trainmen and Motormen 



BY 

FRANK H. DUKESMITH, M. E. 

FORMER SUPERINTENDENT OF AIR BRAKE INSTRUCTION FOR THE 

INTERNATIONAL & GREAT NORTHERN RAILROAD AND 

THE TEXAS & PACIFIC RAILWAY 



^profu^el^ 31llu0trateij 

With Engravings furnished by The Westinghouse Air Brake Company 



PERFECTLY INDEXED and CROSS-INDEXED 




PUBLISHERS 

FREDERICK J. DRAKE & CO. 

CHICAGO, U.S.A. 

1904 




LIBRARY of CONGRESS 

Two Cooles Received 

MAY 7 1904 

Cooyrlffht Entry 

CLA^ ex, xXc. No. 

^11 L 

COPY B 






Entered according to the Act of Congress, in the year of 1904, 

By FREDERICK J. DRAKE & CO. 

in the office of the Librarian of Congress. 



All Rights Reserved. 



Modern Air-Brake Practice— Its 
Use and Abuse 



INTRODUCTION 

The author, realizing that the average Air- 
Brake Instruction book is written in a style much 
too hard for the ordinary reader to understand, 
has endeavored to illustrate the principle on 
which the Air Brake works by drawing compari- 
sons with things commonly met with in the daily 
life of every one, and has avoided technicalities 
as much as possible. 

To still further simplify the study of the brake 
he has divided the subject matter into three dis- 
tinct sections. By this system the reader will 
find that the knowledge necessary for the proper 
handling and care of the air brake can be 
acquired in the shortest possible time and in the 
very easiest manner when compared with any 
other plan. 

Section I treats of the different parts of the 
equipment and their duties. 

3 



4 INTRODUCTION 

Section II explains the various defects arising 
from the use and abuse of the equipment, and 
their remedies. 

Section III is devoted to the Philosophy of 
Air-Brake Handling, in which is brought out 
many important points that have not heretofore 
been made sufficiently clear by air-brake writers; 
together with tables and rules for computing 
Brake Power, Leverage, etc., etc. 

Following each section are carefully selected 
questions and answers, which tend to fasten 
firmly upon the reader's mind every possible 
detail pertaining to the operation and main- 
tenance of the air brake. 

A special feature of this book is the treatment 
given to the subject of Straight Air Brakes used 
on electric-motor cars, thereby affording motor- 
men and others employed on electric-car lines 
the opportunity of acquiring valuable and much- 
needed information. 

As books of instruction are supposed to be 
written for the benefit of the very beginner as 
well as the advanced student, the author has 
endeavored to make each sentence as clear as 
language will permit, even to the extent of 
repeating some things (in a different form of 
expression) in order to meet the comprehension 



INTRODUCTION 5 

of even the dullest student, and in all cases has 
tried to shape the sentences in a style which rail- 
road men generally will readily comprehend, 
without having to guess at anything. 

While it is necessary, of course, in describing 
a drawing of any piece of machinery, to use 
either letters or figures to point out the several 
parts, it is not necessary to be continually refer- 
ring to the letter or figure in speaking of the 
part afterwards, as it gets the reader badly mud- 
dled; but once the letter has pointed out what 
part is meant, in speaking of it afterwards the 
part will be called by its proper name. When a 
certain part is illustrated in this book the letters 
or figures used in referring to it will also be 
placed on the same or opposite page, so that if 
the reader wishes to recall the relation of any 
given part to another he can turn to the engrav- 
ing illustrating that particular piece of machin- 
ery, and will there find an explanation of the 
letters or figures used in referring to it. 

The index is particularly full and complete, so 
that any desired information can be quickly 
found. 



SECTION I 



CHAPTER I 

SOME REASONS WHY THE AIR BRAKE IS SO LITTLE 

UNDERSTOOD BY RAILROAD OFFICIALS 

AND EMPLOYES, AND WHY IT 

IS SO BADLY NEGLECTED 

In writing a book of instruction an author has 
no right to presume upon his reader's previous 
knowledge of the subject, as there is no way of 
his knowing how far that knowledge may extend. 
Therefore, as this book is meant to contain full 
and complete instructions on modern air-brake 
practice, its use and abuse, I will take it for 
granted that you, my reader, are desirous that I 
leave nothing unsaid which may in any way 
throw light on the subject. 

If the human memory could be depended upon 
to reproduce impressions made upon it after the 
manner of a phonograph, it would be the easiest 
thing in the world to acquire an education on 
any given subject, but as this is not the case, we 
must, first of all, bring ourselves to realize that 

7 



8 MODERN AIR-BRAKE PRACTICE 

if the knowledge we acquire is to be of any real 
value to us, we must conform to the natural 
mental laws in our method of acquiring it, if we 
are to have any assurance that our memory will 
reproduce that knowledge at a time when it is 
most needed. 

The mental laws by which the action of the 
mind is mainly controlled are those of Logic and 
Association. This may sound like Greek to you, 
but as it is very essential that you should know, 
at least in a general way, what is meant by the 
laws of Logic and Association, I will explain by 
saying that the truth or falsity of every state- 
ment is determined by Logic, and by the law of 
Association you are enabled to remember and 
trace one circumstance to another. 

To make this plain, if I should say to you that 
the principle on which the automatic air brake 
operates is that any material reduction in the 
trainpipe pressure will cause the brake to set, 
then, if you should see the brake set on a car to 
which no engine was attached, you would logi- 
cally say there must be a leak in the trainpipe 
somewhere, or the pressure could not have been 
reduced. 

That you may understand how the law of 
Association enables you to remember things, I 



ITS USE AND ABUSE 9 

will just ask you to think for a moment of your 
home, and immediately there comes to yoiir 
mind a mental picture of familiar faces, scenes 
and objects that a few minutes ago were buried 
in the depths of your memory. Now, supposing 
you wish to recall some bit of knowledge that 
has apparently slipped your memory, if you can 
take up the thread at any given point, the law of 
Association will carry your thoughts along, step 
by step, until you finally perceive the point you 
had forgotten, and which will cause you to sud- 
denly exclaim, "O, pshaw, I remember now, it's 
so and so!" Now haven't you often gone through 
just this sort of experience? 

Well, then, when you study any subject in a 
systematic way you will find that after you have 
once mastered it you can take it up at almost 
any given point, and by the laws of Association 
and Logic, recall and prove up your previously 
acquired knowledge. 

The air brake is, comparatively speaking, a 
simple piece of mechanism, and as all machinery 
must conform to the laws of Logic in order to 
perform its functions correctly, it will be an easy 
matter for you to master a knowledge of the air 
brake provided you will keep firmly in mind the 
fact that the action of any one part of the appa- 



10 MODERN AIR-BRAKE PRACTICE 

ratus always depends on the action of some 
other part in order to produce a certain result. 
For instance, if you had your train fully charged, 
and the gauge on the engine showed a pressure 
of 70 and 90 pounds, and the angle-cock was 
closed between the tender and the head car, you 
might even throw the handle of the brake valve 
to the emergency position, and still the brakes 
wouldn't set. Why? Simply because the action 
of the triple valve depends on the changing of 
the pressure in the trainpipe, and with the angle- 
cock closed on the head car the brakes couldn't 
set, even if you should knock the engineer's brake 
valve clear off the engine. 

Therefore, when you have mastered a perfect 
knowledge of the air-brake system, the law of 
Association will force you to remember the 
functions of the different parts of the equipment, 
and by the law of Logic you will be enabled to 
tell exactly when the apparatus is working 
properly. 

It may sound strange to make such a state- 
ment, but it is a fact, nevertheless, that the main 
reason why the air brake is so badly neglected is 
because it is automatic, or self-acting. 

The average man, whether he be an official or 
employe, seems to feel perfectly safe on any kind 



ITS USE AND ABUSE n 

of a train so l-ong as he knows it has air brakes 
on it, and if any one were to ask him if he 
thought there was any danger of the brakes fail- 
ing to stop the train, would laugh and say, "O, 
no, not at all, as all the engineer has to do is to 
make an emergency application, and the train 
will stop all right." 

This would be a perfectly true statement if the 
air-brake equipment was always kept in its 
proper condition, but there are so very many 
things that can and do go wrong to prevent the 
brakes from doing their duty that the question 
of keeping them in good order is a very serious 
problem, indeed, and one that is arousing a deep 
interest in the minds of all railroad men. One 
of the strongest evidences of this fact is shown 
in the enactment of the national law spoken of 
elsewhere in this chapter. 

It does not require much of a mechanical mind 
to grasp the fact that an air brake on a car 
would be worse than useless if the packing 
leather in the brake cylinder was dry, and 
allowed the air to escape, for no matter how 
good the engineer might be at handling his 
Drake valve, the brake on that car could not be 
made to hold. 

This is only one of a score of things which 



12 MODERN AIR-BRAKE PRACTICE 

might prevent the brakes from doing their duty, 
but because the brake will ''work itself" the 
majority of men fail to see why the brake should 
not also 'take care of itself." But, like all other 
mechanism, it requires proper attention. 

Another reason why the average man is lulled 
into the belief that the air brake needs but very 
little attention, is because a very few good air 
brakes on a train will produce results simply 
wonderful when compared with the old hand 
brake. 

Such over-confidence in the power of the 
brakes to always stop the train is very much like 
the Irishman who bought two currycombs for his 
horse, because the dealer said to him if he would 
"buy one of his new patent currycombs, he could 
keep his horse on half the usual feed," where- 
upon Pat replied, "Faith, thin, I'll just take two, 
and I won't nade to buy any feed at all, at all." 

Another reason why the air brake is so little 
understood and so badly neglected is because of 
its extreme simplicity, for with just ordinary 
attention it will continue to do its work, with 
more or less efficiency, for a considerable length 
of time, and as a consequence it is neglected 
until the brake-cylinder leather becomes dry and 
worthless; or the piston travel becomes too 



ITS USE AND ABUSE 



13 



great; or the triple valve becomes gummed and 
dirty, and causes the brake to stick; or the 
strainers in the cross-over pipe becomes clogged; 
or the seats of some of the valves become worn 
and leaky, when the brake is "cut out," and the 
weight of that car is left to be stopped by the 
next car on which there happens to be a good 
air brake. But the average man fails to realize 
either the danger or expense of having the 
brakes "cut out," simply because so long as he 
knows a car to have a "self-acting brake" on it 
he feels safe, when as a matter of fact a hand- 
braked car is much safer for the railroad com- 
pany than one with the air brakes cut out. For 
if it were not equipped with air the .car would 
be carried with the non-air cars, and the train 
crew would have to look after it accordingly. 

When short trains and slow speed were the 
order of the day it was perfectly safe to handle 
trains with only one-third of the cars air-braked, 
but in this twentieth century when long trains 
of heavy cars are shot over the country, up and 
down hill, like a Kansas cyclone or a scared 
wolf, the question of stopping power is of the 
highest importance, which means that every car 
in the train should not only have a "quick- 
action" brake on it, but that the brake inust be 



14 MODERN AIR-BRAKE PRACTICE 

in perfect order, and the "piston-travel" right up 
to where it belongs, and the enginemen and 
trainmen possessed of the proper knowledge of 
how best to manipulate and control the brakes 
in order to prevent accidents — as the great 
variety of accidents which may happen from bad 
handling of air brakes is too numerous to men- 
tion. 

It is safe to state that there is not a single rail- 
road of any importance that does not pay out 
annually three times as much money on account 
of bad brakes and bad handling of brakes as 
they pay for a general manager, but because of 
the many different channels through which the 
expenditures are made they are not charged up 
directly to the brakes. 

For instance, an engineer in coming into a 
station with a passenger train is making the stop 
with "one application" (the old way) and, after 
his brake cylinders and auxiliaries have equal- 
ized their pressure, and he is drifting along, 
depending upon the weight of the train to stop 
him at his usual place (because after equaliza- 
tion the brakes cannot be applied any harder), a 
woman or child in crossing the track is killed. 
The amount of money the company has to pay 
out as a result of this "bad handling" of the 



ITS USE AND ABUSE 15 

brakes will run up into thousands of dollars, and 
yet the engineer excuses himself by simply say- 
ing: 'The brakes failed to work." 

Again, railroad companies are out thousands 
of dollars annually on account of damaged mer- 
chandise, caused by the brakes being "thrown 
into the emergency" when there was no real 
danger ahead to require the emergency applica- 
tion to be used, or because of a defective triple 
valve. 

Uneven piston-travel causes more trains to be 
parted while running along, draw-heads pulled 
out, wheels flattened, etc., than any other one 
cause; hence it is evident that the brakes should 
not only be kept in perfect working order at all 
times, but the men who handle them should 
understand thoroughly how to properly manipu- 
late and keep them in order. 

The American Congress, realizing the vast 
importance of having the air-brake equipment 
kept up to somewhere like it should be, recently 
enacted a law, which became effective in Septem- 
ber, 1903, requiring all railroads to have at least 
fifty per cent of the cars in all trains equipped 
with air brakes in good condition. And as the 
law would be a dead letter if the ''good condi- 
tion" clause was not lived up to, it is easy to see 



i6 MODERN AIR-BRAKE PRACTICE 

that railroads are forced to look after the instruc- 
tion of their men as much as possible, and in 
order to do so many roads which are not already 
so provided, are putting on regular air-brake 
instructors as rapidly as conditions will per- 
mit. 

Some idea may be formed of the average 
man's knowledge of the "equalization of pres- 
sure between the brake cylinder and the auxi- 
liary reservoir" by the following true story: A 
certain engineer on a mountain road was going 
down a pretty stiff grade, and after making a 
great number of "reductions" from his train- 
pipe, and not feeling the train slow up as he 
expected, turned to the head brakeman, who 
happened to be riding on the engine, and said: 
"Hey, Bub, you'd better be gittin' back, 'cause I 
ain't got but a few more squirts left in this 
thing." And still he was considered a good run- 
ner by his employers. 

In order to insure safety in the handling of 
trains it is absolutely essential that every one 
whose duties in any way connect him with the 
air brake, should not only know what all the 
parts are that constitute the air-brake equip- 
ment, but must also understand the philosophy 
of handling the brakes under any and all cir- 



ITS USE AND ABUSE 17 

cumstances, as the requirements of his position 
may demand. 

In addition to all of the many reasons previ- 
ously mentioned as to why the air brake is so 
little understood by the average engineman and 
trainman alike, a very common one is because of 
the unsystematic manner in which the study of 
the air brake is usually begun. The engineman, 
if he gives the subject any study at all, usually 
begins by trying to master the mysteries of the 
brake valve, or the pump, and the trainman 
usually thinks there is nothing for him to learn 
except how to "cut it in, or cut it out," and gives 
as his excuse that "the engineer handles the 
brake, and, besides, it is automatic, and works 
itself." 

The experience of late years has abundantly 
proven that if an air-braked train is to be handled 
with safety it is absolutely necessary that every 
man on the train thoroughly understands at 
least the principle on which the brake operates, 
and must be able for a certainty to tell when the 
brakes are in perfect working order by making 
a careful test before starting, or when any 
change is made in the train. 

A serious accident happened recently by the 
simple act of a brakeman turning up the handle 



1 8 MODERN AIR-BRAKE PRACTICE 

of a pressure-retaining valve. He heard the air 
escaping at the "retainer/' and thinking he 
would "stop the leak," turned up the retainer 
handle, and as a consequence the brake on that 
car could not be released from the engine, which 
allowed the wheels to become overheated, caus- 
ing them to burst, which ditched the train and 
killed three men. This would never have hap- 
pened if that brakeman had only understood the 
mere principle on which the brake operates. 



CHAPTER II 

THE AIR-BRAKE EQUIPMENT — THE PARTS AND 
THEIR DUTIES 

The full and complete equipment of a modern 
quick-action automatic air brake is composed of 
twelve essential parts, as follows: 

First: The steam-driven air pump which sup- 
plies the compressed air. 

Second: The main reservoir in which the 
compression air is stored. 

Third: The engineer s brake valve by which 
is regulated the flow of air from the main reser- 
voir into the trainpipe for charging and releas- 
ing the brakes, and from the trainpipe to the 
amostphere for applying the brakes. 

Fourth: The duplex air gauge, which shows 
simultaneously the pressure on the trainpipe 
(black hand), and in the main reservoir (red 
hand). 

Fifth: The pump governor, which regulates 
the supply of steam to the pump, causing it to 
automatically stop when the desired maximum 
of pressure has been accumulated in the air- 
brake apparatus. 

19 



20 MODERN AIR-BRAKE PRACTICE 

Sixth: The trainpipe, which connects the 
engineer's brake valve and each triple valve in 
the train, and includes the air hose and hose 
couplings between cars. 

Seventh: The quick-action triple valve, which 
is connected to the trainpipe, auxiliary reservoir 
and brake cylinder and pressure-retaining valve. 
The triple valve operates automatically when- 
ever the pressure in the trainpipe is reduced 
lower than that in the auxiliary reservoir, and 
performs three functions: charges the aux- 
iliary, applies the brakes and releases the brakes, 
as will be fully explained hereafter. 

Eighth: The auxiliary reservoir, in which is 
stored the air pressure for applying the brake 
(on each car, engine, or tender, there is an indi- 
vidual auxiliary reservoir). 

Ninth: The brake cylinder, in which there is 
a piston and piston-rod, which is connected to 
the brake levers in such a manner that when the 
triple valve is moved to allow the auxiliary pres- 
sure to flow into the brake cylinder, the brake 
piston is thereby forced outward, which causes 
the brakes to apply. 

Tenth: The pressure-retaining valve, which 
is connected to the triple exhaust by a small 
pipe. On freight cars the retaining valve is 



ITS USE AND ABUSE 21 

located on the end of the car near the top, just 
below the staff of the hand brake, and is for the 
purpose of enabling the brakeman to retain a 
pressure of fifteen pounds in the brake cylinder 
while the engineer is recharging the auxiliary 
reservoir. While the handle of the retaining 
valve i^ turned up the brake cannot be released 
from the engine, neither can it be "bled off" by 
the bleed cock of the auxiliary, for the reason 
that the cylinder must discharge its air through 
the triple exhaust, and when the retaining valve 
is closed it means that the triple exhaust is also 
closed. It is very important that brakemen 
thoroughly understand the operation of the 
pressure-retaining valve, as many accidents are 
due to ignorance or negligence in the working 
of this device. 

Eleventh: The automatic slack - adjuster, 
automatically maintains the travel of the brake- 
cylinder piston at a given distance. For instance, 
if the piston-travel is set for eight inches it will 
automatically keep it there. The slack-adjuster 
is piped direct to the brake cylinder, so that 
every time the brake is applied the adjuster is 
operated automatically. 

Twelfth: The air-brake release signal is for 
the purpose of signaling the engineer and train 



22 MODERN AIR-BRAKE PRACTICE 

crew whenever a brake sets, releases or sticks, 
leaks off or has too much piston travel, and 
locates defective triples and enables the train- 
men to release the brake while the train is run- 
ning, without having to get off the car.. It is 
located on the top end of freight cars, opposite 
the end on which is located the pressure-retain- 
ing valve, and, like the slack-adjuster, is piped 
direct to the brake cylinder, so that whenever 
there is sufficient pressure in the brake cylinder 
to apply the brake, the same pressure causes the 
signal to appear above the top of the car in full 
view of the train crew, and when the pressure in 
the brake cylinder is exhausted through the 
triple valve, or leaks out around the packing 
leather in the brake cylinder, the signal is auto- 
matically withdrawn, showing that the brake is 
not set. Should the signal remain up and the 
triple valve fail to release the brake, as it should 
when in perfect condition, the brakeman could 
from the top of a freight or inside of a passen- 
ger car release the brake by simply pressing a 
valve, without having to stop the train, thereby 
avoiding slid-flat wheels, pulled-out draw-heads, 
stalling on grades, heating of wheels, and conse- 
quent wrecks. On flat cars and gondolas the 
signal is shown from the sides of the car, one 



ITS USE AND ABUSE 



23 



on each end. On passenger trains the signal is 
located at the side of the door in both ends of 
the car, so that the signal can be seen at once 
by the conductor or brakeman, regardless of the 
direction in which they might be going when 
passing through the train. 

As the very heart of the automatic air-brake 
equipment is the triple valve, it is necessary that 
both enginemen and trainmen thoroughly mas- 
ter this feature first of all. 

It is not necessary that trainmen should know 
all about the care of the pump, the ports in the 
brake valve nor how to handle the air as an 
engineer, but they should know and understand 
all about the triple valve, and be able to make 
an intelligent report of any defects that may be 
found in the car equipment, how to make a 
proper test, and why correct piston travel is 
positively essential to good brakes. 

Enginemen should not only be thoroughly 
familiar with the points just outlined for train- 
men to learn, but, in addition, should know all 
about the action of the pump and the pump gov- 
ernor; the brake-valve, its several parts and 
their action; how to determine and maintain the 
proper braking power on engine and tender; the 
construction and operation of the whistle-signal 



24 MODERN AIR-BRAKE PRACTICE 

apparatus; why different air pressures are neces- 
sary; the best manner of handling different trains 
under any and all circumstances, and how to 
detect and report intelligently any trouble that 
may arise in any part of the equipment. 

To the ordinary mind this may at first thought 
appear very difficult of accomplishment, bu': 
such, however, is not the case, provided the 
study of the air brake is taken up systematically, 
and one thing is mastered at a time, taking each 
part in its regular order. 

This cannot be done in a minute or a month, 
but requires time and patience. There is noth- 
ing mysterious about the air brake, as it is simply 
a question of one pressure working against 
another at all times, and all there is to learn is 
how and when the several pressures are sep- 
arated or joined together, and when and to what 
extent you wish to let the pressures flow together 
or be kept apart, in order to secure a given 
result. 

All this is done by a system of very simple 
valves and pistons, reservoirs and cylinders, all 
connected by suitable pipes for the purpose of 
allowing the compressed air to pass from one 
part of the equipment to the other, or to the 
atmosphere, as the case may be. 



ITS USE AND ABUSE 25 

The first part of the air brake equipment we 
will consider will be 

THE TRIPLE VALVE 

Naturally the first question you will ask is, 
"Why must there be a triple valve?" 

It is because the brake charges, sets and 
releases automatically, and as this requires three 
distinct services, it follows that a device capable 
of doing a triple service must be had, and as 
these three things are done by one part of the 
equipment it is called the triple valve (meaning 
three valves in one, or a valve that charges the 
auxiliary reservoir, a valve that sets the brakes 
and a valve that releases the brakes). 

As there are several kinds of triple valves in 
use, but as the same principle operates them all, 
I will first describe the action of the "plain" 
triple in making a full service application of the 
brakes, releasing the brakes and recharging the 
auxiliary reservoir (taking it for granted that 
the auxiliary and trainpipe are charged to begin 
with). 

In order to clearly understand the duties and 
action of the triple you must always bear in 
mind that on each car there must be a train- 
pipe, an auxiliary reservoir, a brake cylinder and 
the triple valve. 



26 MODERN AIR-BRAKE PRACTICE 

The trainpipe is the channel through which 
the compressed air passes between the engineer's 
brake valve and the triple. 

The auxiliary reservoir is where the air is 
stored under each car, ready for use. 

The brake cylinder is where the air is applied 
in setting the brakes, and the triple valve per- 
forms the triple duty of charging the auxiliary, 
applying the air to the brake cylinder and releas- 
ing the air from the brake cylinder. 

But before describing the air brake let us draw 
a comparison with something that will help to 
fix in our mind what action must take place in 
order to set the brake. 

The best thing to compare the air brake with 
in order to exemplify the principle on which it 
operates, is a bottle of soda pop, for the reason 
that gas is mixed with the soda when it is bot- 
tled. A bottle of champagne would make a 
better comparison, owing to the higher pressure 
with which the wine is bottled, but as it is a little 
too expensive for the average railroad man to 
become very familiar with, I will just use the 
ordinary bottle of soda pop. 

If you wanted to fill a glass with pop, the first 
thing you would have to do would be to break 
the wire that holds the cork, when the pressure 



ITS USE AND ABUSE 27 

in the bottle would force the cork out and let 
the soda flow into the glass. 

Therefore, figuratively speaking, the brake 
cylinder represents the glass, the auxiliary the 
bottle, the compressed air in the auxiliary the 
soda, the triple valve the cork and the trainpipe 
pressure the wire, and when you take the train- 
pipe pressure away from the triple (or break the 
wire that holds the cork), the pressure that is in 
the auxiliary forces the triple out and lets the 
air pass from the auxiliary into the brake cylin- 
der and sets the brake, by forcing the cylinder 
piston out against the levers, which in turn forces 
the shoes up against the wheels. 

By this you will understand that in order to 
set the brakes the pressure in the trainpipe 
must be 7'educed lower than that in the auxiliary, 
otherwise the triple would not move and open 
the port between the auxiliary and brake 
cylinder. 

The Parts of the Plain Triple Valve consist of 
only six things, besides the casing which holds 
them all, and are shown in plate i (which shows 
the way the new plain triple now used for driver 
brakes would look if it was cut in half), and they 
are designated as follows: 23 is called the triple 
piston; 24 is the slide valve; 25 is the graduating 



28 MODERN AIR-BRAKE PRACTICE 

valve; 26 is the gr^^duating stem, and 27 is the 
graduating spring; 32 is the U spring over the 
slide valve. 

The casing is so shaped that one part of it 
forms a cylinder for the triple piston to move in, 
and is marked B, and adjoining it is a chamber 
having a flat side (called the slide valve seat), 
for the slide valve to slide on, and is marked C. 

The flat side of this chamber, which forms the 
seat on which the slide valve rests, has two ports 
cut through it; the one marked / leads to the 
brake cylinder, and the other, marked h, leads 
to the atmosphere. 

In the slide valve there are also two ports; 
one passes clear through the valve, as shown by 
the letters /, p-p, and the other is a groove cut 
in the bottom of the valve, and marked ^, and 
when the valve is moved toward the left end of 
chamber C (in other words, moves down), the 
port through the valve marked p connects with 
the port in the seat marked/, so that the air in 
the auxiliary can pass through the valve and 
valve seat and on through pipe connection X 
directly into the brake cylinder; and when the 
slide valve is in the opposite end of chamber C 
the groove ^ in the bottom of the slide valve 
connects the two ports /and h together, so that 



ITS USE AND ABUSE 29 

one end of the groove rests directly over the 
port leading to the brake cylinder, and the other 
end rests over the port leading to the atmos- 
phere, thus forming a direct opening between 
the brake cylinder and the atmosphere; there- 
fore, as the triple is so connected to the auxiliary 
by pipe connection Y that the auxiliary pressure 
is always in direct communication with chamber 
C, in which the slide valve moves, and as the 
port in the seat marked /is the only way for the 
air to get in or out of the brake cylinder, with 
this kind of a triple, it is very evident that when 
the slide valve is moved along on its seat until 
the port in the valve marked p-p comes opposite 
the port in the seat marked /, the air in the 
auxiliary is free to pass into the brake cylinder, 
and set the brake. And when the slide valve is 
forced back again to its original position, as 
shown in plate i, the air in the brake cylinder is 
free to pass out to the atmosphere through ports 
/ ^, h and exhaust port k, and thereby release 
the brakes. Therefore, as the flow of air from 
the auxiliary to the brake cylinder, and from the 
brake cylinder to the atmosphere is dependent 
upon the movement of the slide valve, it is neces- 
sary that you next understand how this move- 
ment is accomplished. 



30 



MODERN AIR-BRAKE PRACTICE 



4 Pi PC TAP 
10 AUXIUARY RESERVOIR 




PLATE NO. 1 — NEW STYLE PLAIN TRIPLE- VALVE. 



ITS USE AND ABUSE 31 



DESCRIPTION OF PLATE I — NEW DRIVER BRAKE 
PLAIN TRIPLE 

W is the trainpipe connection. 
X is the cylinder connection. 
Y is the auxiliary connection. 

23. Triple piston and stem. 

24. Slide valve. 

25. Graduating valve. 

26. Graduating stem. 

27. Graduating spring. 

30. Triple piston packing ring. 
32. U, or slide valve spring. 
The air passages and ports are explained in 
the text. 



32 MODERN AIR-BRAKE PRACTICE 

The stem of the triple piston extends into 
chamber C, in which the slide valve moves, and 
the valve is hung on this stem; there is a pack- 
ing ring (30) around the triple piston, making a 
tight joint against the walls of cylinder B, and as 
one end of this cylinder is always open to cham- 
ber C (which always contains auxiliary pressure), 
and the other end of cylinder B is always open 
to the trainpipe, you will at once see that the 
triple piston stands between the auxiliary and 
trainpipe pressure at all times, and if these 
pressures are equal, and the piston is in full 
release position, as shown in plate i, should the 
pressure on the trainpipe side of the piston 
become lower than that on the slide valve side, 
the piston would be moved by the auxiliary 
pressure, and of course draw the slide valve with 
it, causing the port in the valve marked p to 
come opposite the port in the seat marked/, and 
allow the air from the auxiliary to pass into the 
brake cylinder and set the brake. 

Now that the air is in the brake cylinder, the 
next point to learn is how to release the brake. 

To Release the Brake it is necessary to force 
the slide valve back to the position it occupied 
before the brake was set, as shown in plate i. 

To do this we use the pressure stored in the 



ITS USE AND ABUSE 33 

main reservoir, on the engine, for when the 
engineer places his brake valve in full release 
position the main reservoir pressure quickly 
raises the pressure on the trainpipe side of the 
triple piston and forces it back to the position 
shown in plate No. i, and, as the slide valve has 
to go back with it, the groove £" in the bottom of 
the valve is placed so that one end of it rests 
over the port marked /in the valve seat, and the 
other end rests over the port marked h in the 
valve seat, consequently the air in the brake 
cylinder is free to pass out to the atmosphere 
through ports f, ^, h and through a passage 
around the casing to the triple exhaust marked 
k. The air having thus escaped from the brake 
cylinder the heavy spring in the cylinder, marked 
9, in plate 7, drives the brake piston back from 
the levers, which allows the shoes to drop away 
from the wheels, and the brake is released. 

The whistling noise heard when the brakes 
are releasing on passenger cars is caused by the 
air escaping through the small ports in the triple 
(on freight cars the air exhausts through the 
pressure-retaining valve on top of the car), and 
if this whistling is weak, when releasing after a 
full application has been made, it indicates that 
either a portion of the air has already escaped 



34 MODERN AIR-BRAKE PRACTICE 

from the cylinder through a bad packing leather 
around the brake piston, or there is too much 
piston travel, which allowed the air to expand 
in the cylinder more than it should have done; 
in other words, a high pressure will rush out 
quicker than a low pressure, for, as you know, 
the faster wind blows the louder it whistles. 

Recharging the Auxiliary. — Having set the 
brakes and released them, it now becomes neces- 
sary to recharge the auxiliary reservoir, to be 
ready for the next application. 

You must keep in mind that the brake cylm- 
der gets its power from the auxiliary, and the 
latter must always be kept charged ready to 
meet all demands made upon it by the cylindero 
If the auxiliary is only partly charged, the force 
with which the brakes set will be correspond- 
ingly weak. 

Also remember that just as soon as the slide 
valve moves to let the air out of the brake cylin- 
der that in doing so the feed grooves between 
the trainpipe and auxiliary are opened to admit 
air again into the auxiliary. 

You will now look at plate i, and trace the 
course of the air from the trainpipe through the 
triple to the auxiliary. ' 

Begin at the point indicated by W, and follow 



ITS USE AND ABUSE 35 

the arrows; you will notice the air travels 
through a passage (a-a) in the casing, to a cham- 
ber indicated by A, and from this chamber there 
are two openings (c, c,), which allow the air to 
pass into the cylinder in which the triple piston 
moves, as indicated by B. As the air passes 
from chamber A it strikes the plain side of the 
triple piston and forces it to the extreme end of 
cylinder B, and as the piston is supposed to be a 
tight fit in cylinder B, the only chance the air has 
to get into chamber C is by passing through a 
small groove cut in the wall of cylinder B, as 
indicated by 7u. This is called the "feed groove." 
As this groove 7n is only as long as the head of 
the piston is thick, you will at once see that the 
piston must be all the way back before the air 
can enter this groove; you will also notice that 
the piston only forms a seat about half way from 
its center to its outer edge; in other words, there 
is a shoulder on the slide valve side of the pis- 
ton, and this necessitates another groove to be 
cut in this shoulder, which is shown by the let- 
ter 71. The air can now pass from cylinder B by 
way of the feed grooves, 7n and n, into chamber 
C, and over the top of the slide valve through 
the pipe connection Y into the auxiliary. 

In order, therefore, to make it plain to you 



36 MODERN AIR-BRAKE PRACTICE 

how the auxiliary is charged to its proper pres- 
sure of seventy pounds to the square inch, we 
will just suppose that the pump on the engine 
(which, when modern brake valves are used, is 
controlled by the main reservoir pressure) will 
only pump up to seventy pounds pressure, and 
no more; in other words, the pump will keep 
working until all the space into which the com- 
pressed air from the pump is allowed to flow is 
filled to seventy pounds before it stops. 

If the space to be filled by the pump is merely 
the main reservoir, the pump will stop when the 
main reservoir is charged to seventy pounds, 
provided the governor is set at seventy; but if 
the engineer places the handle of his brake 
valve in position so that the air in the main reser- 
voir can flow direct into the trainpipe, it means 
that there is just that much more space to be 
filled before the pump will stop; then if the 
auxiliary is cut into the trainpipe, by opening 
the cut-out cock on the cross-over pipe, it means 
that there is still more space for the air to flow 
into, and as the pump will not stop until there is 
seventy pounds in the main reservoir, and as the 
main reservoir cannot get its seventy pounds 
until the trainpipe has its seventy pounds, and 
as the trainpipe cannot get its seventy pounds 



ITS USE AND ABUSE 37 

until the auxiliary gets its seventy pounds, it fol- 
lows that the pump will continue to work 
until the auxiliary, trainpipe and main reser- 
voir are all equally charged up to seventy 
pounds, for the reason that air, like water, will 
continue to flow until it finds its level, and 
when we speak of the pressure being "equal- 
ized" we mean that they have come to a level 
with each other. 

Owing to the smallness of the feed groove in 
the triple through which the air passes to get 
into the auxiliary, the trainpipe will naturally 
fill quicker than the auxiliary, and cause the 
pump to stop temporarily, but as soon as the 
trainpipe pressure is again lowered by the air 
passing through the feed grooves into the aux- 
iliary, the pump will again start, and continue to 
compress air until every bit of space is filled to 
seventy pounds. 

If the main reservoir, trainpipe or auxiliary 
reservoir leaks, while the brake valve is in the 
position we are now speaking of, the pump will 
not stop at all, and a great many leaks will very 
soon wear a pump out. 

Right here I will mention a few important 
things to remember when charging up a train: 
first, leaks of any kind will prevent getting the 



38 MODERN AIR-BRAKE PRACTICE 

required pressure in the time it should be got- 
ten, and bad leaks will prevent it entirely. 

Second, the strainer and feed grooves in the 
triple must be kept clean to allow the air to pass 
freely. 

Third, the packing ring around the triple pis- 
ton must be a good fit to prevent the auxiliary 
charging too rapidly, and to insure against 
charging too quickly is the reason for having a 
shoulder on the slide valve side of the piston, 
for if any air leaks around the packing ring it 
cannot enter the auxiliary except through the 
second feed groove, as shown by n in plate i, 
unless the shoulder on the piston has a bad seat. 

A still greater reason for having the packing 
ring (30) tight, is to insure the brake against 
"sticking," as it will if the trainpipe pressure 
equalizes with the auxiliary without moving the 
slide valve. 

The reason for having the feed grooves so 
small in the triples is to allow all the auxiliaries 
on the train to charge as nearly together as pos- 
sible, and also to assist in making the triple 
sensitive to the slightest reduction of trainpipe 
pressure, for, if the feed groove was large, when 
the air was drawn from the trainpipe a con- 
siderable amount of air from the auxiliary would 



ITS USE AND ABUSE 39 

flow back into the trainpipe before the piston 
moved; but, as it is, the feed groove is so small 
and so short that it requires less than a two 
pound reduction to cause the triple piston to 
move and shut off communication between the 
auxiliary and trainpipe. 

For the same reason (sensitiveness) the piston 
packing ring must have a good fit, or else the 
auxiliary and trainpipe pressures will equalize, 
and thereby fail to move the piston when desired 
in setting or releasing the brakes. This is espe- 
cially true on long trains. 

If everything was tight, and all the parts 
working as they should, and trainpipe pressure 
was kept constantly at seventy pounds, you could 
charge a one hundred car train as quickly as you 
could one car, as under such perfect condition 
the air will pass through the feed grooves at the 
rate of one pound a second, but as this is never 
the case in actual practice, it will take about five 
minutes to charge up a short train of ten cars, 
and about twelve to fifteen minutes for a train of 
thirty or forty cars, with comparatively no train- 
pipe leaks, and where there are leaks it natu- 
rally takes much longer. 

Always fight trainpipe leaks like you would a 
rattlesnake, as this trouble does more to pre- 



40 MODERN AIR-RRAKE PRACTICE 

vent the proper action of the brakes than any 
other one thing. 

So far I have only had occasion to speak of 
but one kind of an application of the brakes, 
and that is "full service application"; but there 
are three kinds of applications, which will be 
fully explained in their proper place: one is 
called **full service application," one is called 
''partial service application," and the third is 
called "emergency application." 

As yet I have only described the duties of the 
triple piston and the slide valve, but there are 
four other parts to the plain triple that must 
now be explained to you, which you will see by 
again referring to plate i, and designated as 
follows: 

The graduating valve, which works in the slide 
valve, is marked 25; the graduating stem is 
marked 26, and the graduating spring which 
surrounds it and holds it to its seat is marked 27; 
the U spring is marked 32. Now let us see why 
we need these parts. 

The graduating valve is what enables us to 
make a partial service application, for without it 
the pressure in the auxiliary reservoir would be 
reduced much below that in the trainpipe, after 
a ten pound reduction, before the triple would 



ITS USE AND ABUSE 41 

lap itself, as there would be nothing to stop the 
flow of air from the auxiliary into the brake 
cylinder, until the auxiliary pressure becomes 
low enough for the trainpipe pressure to over- 
come the friction on the seat of the slide valve; 
but with the graduating valve in good condition, 
when a reduction of say ten pounds is made on 
the trainpipe, the triple will automatically lap 
itself as soon as a fraction over ten pounds has 
left the auxiliary. 

This is done as follows: when the trainpipe 
pressure is reduced below that in the auxiliary 
the triple piston moves and carries with it the 
graduating valve, for, as you will see by looking 
at plate i, the graduating valve is connected 
directly to the stem of the triple piston by a 
small pin, as shown by the dotted lines, and, 
when the piston moves, the graduating valve is 
carried from its seat in the slide valve and opens 
port /, so that when the slide valve is in service 
position the auxiliary air can pass through the 
slide valve by way of ports / and p, then through 
port / in the seat of the slide valve and on 
through pipe connection X direct into the brake 
cylinder; as only ten pounds was drawn from the 
trainpipe, just as soon as a fraction over ten 
pounds flows from the auxiliary, the trainpipe 



42 MODERN AIR-BRAKE PRACTICE 

pressure being now the strongest forces the 
triple piston towards the auxiliary end of its 
cylinder, but it can only force it a very short 
distance, for the reason that the distance between 
the end of the slide valve and the shoulder on 
the stem of the piston is only three-sixteenths of 
an inch, and when the piston has moved this dis- 
tance it is stopped by the slide valve, because the 
auxiliary pressure, aided by the U spring, is 
firmly holding the slide valve, on account of the 
friction being greater on the slide valve seat 
than it is around the edge of the triple piston, 
and when the piston is thus stopped by the slide 
valve, the graduating valve is now back on its 
seat, and no more air can flow from the auxiliary 
into the brake cylinder, until the trainpipe pres- 
sure is again reduced and the graduating valve 
again unseated by the movement of the triple 
piston. 

The slide valve does not move when the 
second reduction is made, but stands in the 
same position it assumed on the first reduction. 
Consequently, as soon as the graduating valve is 
unseated the air will again flow into the brake 
cylinder; but when the air in the brake cylinder 
finally becomes as strong as it is in the auxiliary 
(or equalizes) the pressure in the auxiliary no 



ITS USE AND ABUSE 43 

longer falls below that In the trainpipe, and 
therefore the graduating valve remains off its 
seat, because the triple piston does not now 
move back as it did when the first reduction was 
made, as the pressure in the trainpipe is now as 
low or lower than it is in the auxiliary, and the 
brakes are now fully applied. 

Hence we can make a full service application 
without the graduating valve, but we must have 
this valve in making a ''partial service applica- 
tion." 

If the engineer simply wants to slow his train 
up, but does not want to come to a full stop, he 
can draw off any amount of air from the train- 
pipe he desires, and when he laps his brake 
valve, the triple valve will, by means of the 
graduating valve, let a corresponding amount of 
air from the auxiliary into the brake cylinder 
and automatically lap ports l-p-p in the slide 
valve, but if the engineer should draw his train- 
pipe pressure down below the point at which the 
auxiliary and brake cylinder equalize, he would 
not only be wasting the trainpipe pressure, but 
would have trouble when it came time for him 
to release his brakes as will be explained later 
on. 

We now understand what the graduating valve 



44 MODERN AIR-BRAKE PRACTICE 

is for; now let us see what the graduating stem 
and spring has to do with it. 

As I have already mentioned, the third kind 
of an application is called the "emergency." 
When this kind of application is made it is 
only in case of danger, and therefore it is desired 
that the air in the auxiliary should be passed 
into the brake cylinder as quickly as possible, 
and in order to do this it is necessary to have 
the entire slide valve clear the port in the seat 
through which the air has to pass. 

In making ordinary stops this very quick 
action is not required, and in order to prevent 
the slide valve making the full stroke, there is a 
projection on the trainpipe side of the triple pis- 
ton which strikes against the graduating stem 
(26), and as this stem is held to its seat by the 
graduating spring (27), the strength of this spring 
combined with the pressure in the trainpipe 
causes the triple piston to stop, and in doing so 
the slide valve is held in such a position that 
port p is in register with port /, and of course 
the brakes are applied gradually. 

But if the pressure in the trainpipe is reduced 
suddenly, the auxiliary pressure causes the triple 
piston to strike the graduating stem a hammer 
blow and overcomes the tension of the spring 



ITS USE AND ABUSE 45 

so that the slide valve entirely clears the port in 
the seat, and the auxiliary pressure immediately 
equalizes with the brake cylinder. (This refers 
to the plain triple. The emergency action of 
the quick-action triple will be described later 
on.) 

The U spring (32) is placed over the slide 
valve for the reason that if the brake is applied 
and all the air is let out of the trainpipe, and 
the car cut off from the engine, the brake could 
not be "bled" off by the release valve on the 
auxiliary if the slide valve could not be lifted off 
its seat by the brake cylinder pressure, but as 
there is a slight lift to the slide valve for this 
purpose, the U spring is required to reseat the 
valve, so that when the auxiliary is again 
recharged no air can get under the slide valve 
and pass out to the atmosphere through port h 
in the valve seat. 

If there is a great deal of oil on the slide valve 
seat it will prevent the slide valve from being 
forced up by brake cylinder pressure, when a 
single car is being "bled off," and the brake can- 
not be released at all until the air finally leaks 
out around the packing leather in the cylin- 
der. In such a case the release signal is very 
handy. 



46 MODERN AIR-BRAKE PRACTICE 

THE QUICK-ACTION TRIPLE VALVE 

So far I have only spoken of the plain triple, 
but as all cars are now supposed to be equipped 
with the "quick-action triple" we will next ascer- 
tain what is the difference between the two kinds 
of triples, and what the advantage is in having 
the quick-action triple. 

When an engineer applies the brakes he has 
to draw the trainpipe pressure down by letting 
it escape to the atmosphere through a port in 
the brake valve, and as the triple pistons will 
not move until the trainpipe pressure is reduced 
below that in the auxiliary reservoirs, it naturally 
follows that on a train, of say thirty cars, equipped 
with plain triples, the brakes on the head end 
will set before the ones on the rear end, for the 
reason that the air in the front end of the train- 
pipe has to get out of the way before the air in 
the rear end can escape, and whenever the pres- 
sure on the trainpipe side of any triple is 
reduced lower than the auxiliary side, that 
triple will move and set the brake at once, and 
the difference between the plain and the quick- 
action triple is that the trainpipe pressure can 
be reduced faster with a "quick-action" triple 
than it can with a plain one, and consequently 



ITS USE AND ABUSE 47 

the brakes on a long train can be applied more 
rapidly with "quick-action" triples. 

To make this plain to you, suppose you were 
in a crowded opera house and a cry of "fire" 
was heard, as it recently happened in Chicago, 
everybody would make a rush for the front door 
at once, but as the door would only let so many 
out at a time, those in the rear would have to 
wait until those in front got out first, and if it 
was a bad fire the result would be a horrible 
catastrophe. This refers to the plain triple. 

Now suppose that the opera house was so 
built that in addition to the regular front 
entrance there was another big door in the side 
of the building which opened into a large hall, 
then when the cry of fire was heard a portion of 
the audience would escape through the regular 
front entrance and the others would get out 
through the side door, thus emptying the burn- 
ing building so quickly that everybody is saved. 
This refers to the quick-action triple, for with 
the plain triple there is but one way of getting 
the trainpipe pressure away from the triple pis- 
ton, and that is through the brake valve (the 
front door), but with the quick-action triple there 
is an extra outlet through which the trainpipe 
pressure can escape when an emergency appli- 



48 MODERN AIR-BRAKE PRACTICE 



I Brake OyUate 



PLATE NO. 2 QUICK-ACTION TRIPLE IN RELEASE AND CHARGING 

POSITION. 



ITS USE AND ABUSE 



49 



DESCRIPTION OF PLATE 2 — QUICK-ACTION TRIPLE 
VALVE, RELEASE AND CHARGING POSITION 

A. Trainpipe connection. 

B. Auxiliary reservoir connection. 

C. Cylinder connection. 

3. Slide valve. 

4. Triple piston and stem. 

5. Triple piston packing ring. 

6. U or slide valve spring. 

7. Graduating valve. 

8. Emergency valve piston. 

9. Emergency valve seat and guide. 
10. Rubber seated emergency valve. 
12. Check valve spring. 

14. Check gasket. 

15. Check valve. 

21. Graduating stem. 

22. Graduating spring. 

23. Triple gasket. 

The air passages and ports are described in the 
text. The feed groove, i, is now open. 



50 MODERN AIR-BRAKE PRACTICE 

cation is made, and thus cause the brakes on the 
entire train to be applied in about two seconds. 
This extra outlet is called the ''emergency 
valve," and will be explained when I describe 
plate 5. 

The parts contained in the quick-action triple 
which are not in the plain one, are shown in 
plates 2, 3, 4 and 5, and are indicated as follows: 
The emergency piston is marked 8; the guide 
for this piston, which also forms a seat for the 
emergency valve, is marked 9; the emergency 
valve is 10; the check-valve spring is 12; the 
check valve is 15, and the gasket which sep- 
arates chamber X from chamber Y is marked 14. 
This gasket, you will notice, extends clear across 
the triple, but a portion of it is cut away just 
over the emergency valve, so that when that 
valve is unseated, as it is in an emergency appli- 
cation, the air in chamber Y can pass into cham- 
ber X and the brake cylinder, and another hole 
is cut in this same gasket at ^, so that the train- 
pipe pressure, which enters the triple at A, can 
pass freely into chambers/* and h, 

PLATE 2 — QUICK -ACTION TRIPLE IN RELEASE AND 
CHARGING POSITION 

The quick -action triple has five positions: 
release, charging, service, lap and emergency. 



ITS USE AND ABUSE 



51 



Release and charging positions are really one 
and the same, and are shown in plate 2. While 
the air is being released from the brake cylinder 
by way of the ports in the slide valve seat, etc., 
as previously described in plate i, the auxiliary 
is being charged by way of the feed grooves 
described in plate i as nt and n^ but in plate 2 
they are marked i and k. 

In plate 2 you will observe that a different set 
of figures and letters are used from those 
employed in plate i, to point out the different 
ports, etc., but this need not worry you, for, as 
the poet says, "a rose by any other name would 
smell just as sweet," and whether you call it 
cylinder h, as in plate 2, or B, as in plate i, you 
know that it is the cylinder in which the triple 
piston moves. So, to clear you up on this point, 
notice that in plate 2 the trainpipe connection 
to the triple is marked A, while in plate i it 
is W. Now look at the arrows in plate 2 and 
you will see that after the air enters the triple at 
A it passes through a passage in the casing, the 
same as in plate i, to a chamber having two 
openings into the cylinder containing the triple 
piston, just like plate i, and from this cylinder 
the air passes through the same two feed 
grooves that in plate i are marked m and n, but 



52 MODERN AIR-BRAKE PRACTICE 

in plate 2 are marked / and k, on into the slide- 
valve chamber, and instead of entering the aux- 
iliary at the pipe connection Y, as in plate i, it 
passes right on through the slide-valve chamber 
into the auxiliary, so you see whether it is a 
plain or quick-action triple the auxiliary pres- 
sure is always on the slide-valve side of the 
triple piston, and trainpipe pressure is on the 
opposite side. 

Having familiarized yourself with the parts of 
the triple as described in plate i, you will see by 
plate 2 that the same parts are contained in the 
quick-action triple, and perform the same duties, 
so that the only difference between the two 
kinds of triples is the emergency attachment 
(which I have explained by reference to Figs. 
8, 9, 10, 12, 14 and 15), and in charging an aux- 
iliary or releasing a brake the air has to travel 
the same routes whether a plain or quick-action 
triple is used, but in setting the brakes in emer- 
gency is where the difference comes in between 
the two kinds of triples. (See plate 5.) 

PLATE 3 — SERVICE POSITION OF QUICK-ACTION 
TRIPLE VALVE 

In this position you will notice that the triple 
piston has moved in its cylinder until the projec- 



ITS USE AND ABUSE 53 

tion/ strikes against the graduating stem, which 
stops it, and in making this movement the stem 
of the piston has drawn the slide valve to a posi- 
tion which places the port marked Wy z-z in 
register with the port in the seat marked r, thus 
allowing the auxiliary pressure to pass into the 
brake cylinder through pipe connection C and 
set the brake. (If this is not perfectly clear to 
you, read again what I said about setting the 
brakes in my description of plate i.) 

PLATE 4 — LAP POSITION OF QUICK-ACTION TRIPLE 

Lap position means that all ports are closed, 
and the reason why the triple automatically laps 
itself is due to the fact that when the slide valve 
is moved to service position the graduating 
valve is held off its seat at w by the triple pis- 
ton and when the pressure in the auxiliary 
becomes a little less than trainpipe pressure the 
piston is forced back by the trainpipe pressure 
until the graduating valve strikes its seat in the 
slide valve, and stops the flow of the auxiliary 
air into the brake cylinder. 

The reason the slide valve is not moved when 
the graduating valve moves is because the aux- 
iliary and trainpipe pressures are so nearly 
equal that the friction of the slide-valve seat, 



54 MODERN AIR-BRAKE PRACTICE 




PLATE NO. 3 — QUICK-ACTION TRIPLE IN SERVICE POSITION. 



ITS USE AND ABUSE 55 



DESCRIPTION OF PLATE 3 — QUICK-ACTION TRIPLE 
VALVE, SERVICE POSITION 

A. Trainpipe connection. 

B. Auxiliary reservoir connection. 

C. Cylinder connection. 

3. Slide valve. 

4. Triple piston and stem. 

5. Triple piston packing ring. 

6. U or slide valve spring. 

7. Graduating valve. 

8. Emergency valve piston. 

9. Emergency valve seat and guide. 
10. Rubber seated emergency valve. 
12. Check valve spring. 

14. Check gasket. 

15. Check valve. 

21. Graduating stem. 

22. Graduating spring. 

23. Triple gasket. 

The feed port, i, is now closed. 



56 MODERN AIR-BRAKE PRACTICE 




AimricanJaaeltinitt 



PLATE NO. 4 — QUICK- ACTION TRIPLE IN LAP POSITION. 



ITS USE AND ABUSE 57 



DESCRIPTION OF PLATE 4 — QUICK-ACTION TRIPLE 
VALVE, LAP POSITION 

A. Trainpipe connection. 

B. Auxiliary reservoir connection. 

C. Cylinder connection. 

3. Slide valve. 

4. Triple piston and stem. 

5. Triple piston packing ring. 

6. U or slide valve spring. 

7. Graduating valve. 

8. Emergency valve piston. 

9. Emergency valve seat and guide. 
10. Rubber seated emergency valve. 
12. Check valve spring. 

14. Check gasket. 

15. Check valve. 

21. Graduating stem. 

22. Graduating spring. 

23. Triple gasket. 

All ports are now closed. 



58 MODERN AIR-BRAKE PRACTICE 

combined with the tension of the sHde valve 
spring (marked 6, in plate 5), prevents it, and as 
this keeps the exhaust port closed, and the posi- 
tion of the triple piston keeps feed groove i 
closed, all ports are now closed and the valve is 
said to be on lap. 

Remember, the triple will not lap itself unless 
the auxiliary pressure has a chance to get lower 
than trainpipe pressure, which means that if an 
engineer reduces his trainpipe pressure below 
the point at which the auxiliary and brake- 
cylinder pressures equalize, the only means of 
holding the air in the brake cylinder (aside from 
the packing leather around the brake piston and 
the closing of the triple exhaust) is the check 
valve (15), or the packing ring (30) of the triple 
piston, for while it is true that the piston would 
seat against gasket 23, still this gasket so soon 
becomes hard that it cannot be relied upon to 
stop the auxiliary pressure from flowing back 
into the trainpipe. 

The reason the check valve has to be depended 
upon to keep the brake-cylinder pressure from 
flowing back into the trainpipe, after an extra 
heavy reduction has been made, is because nine 
times out of ten the air in chamber Y will reduce 
as fast as the trainpipe pressure is reduced, on 



ITS USE AND ABUSE 59 

account of the volume in Y being so small that 
the slightest possible leak in the seat of the 
check valve will let it out, and after the train- 
pipe pressure has been drawn down sufficient to 
allow the auxiliary and brake cylinder to equal- 
ize, the leak from chamber Y is supplied by the 
brake cylinder, for whenever the pressure in Y 
becomes less than that in the brake cylinder the 
emergency valve (10) is forced off its seat by the 
brake-cylinder pressure until it equalizes again 
with chamber Y, when the spring (12) reseats 
valve 10, which is done very quickly, conse- 
quently if the trainpipe pressure was entirely 
exhausted and the check valve leaked very bad 
the brake cylinder would very quickly be robbed 
of its pressure, and let the brake off. It is, 
therefore, very bad practice to ever reduce the 
trainpipe pressure below the point at which the 
auxiliary and brake cylinder equalizes, except in 
an emergency. 

In making an emergency application the check 
valve is raised off its seat 120 times a second. 

PLATE 5 — EMERGENCY POSITION OF QUICK-ACTION 
TRIPLE VALVE 

A sudden reduction of trainpipe pressure is 
necessary to cause the triple to assume emer- 
gency position. 



6o MODERN AIR-BRAKE PRACTICE 




PLATE NO. 5 — QUICK-ACTION TRIPLE IN EMERGENCY POSITION 



ITS USE AND ABUSE 6l 



DESCRIPTION OF PLATE 5 — QUICK-ACTION TRIPLE 
VALVE, EMERGENCY POSITION 

A. Trainpipe connection. 

B. Auxiliary reservoir connection. 

C. Cylinder connection. 

3. Slide valve. 

4. Triple piston and stem. 

5. Triple piston packing ring. 

6. U or slide valve spring. 

7. Graduating valve. 

8. Emergency valve piston. 

9. Emergency valve seat and guide. 
10. Rubber seated emergency valve. 
12. Check valve spring. 

14. Check gasket. 

15. Check valve. 

21. Graduating stem. 

22. Graduating spring, 

23. Triple gasket. 



62 MODERN AIR-BRAKE PRACTICE 

When a sudden reduction is made it causes 
the triple piston (4) to strike the graduating stem 
(21) such a hammer blow that the graduating 
spring (22) is unable to stop it from making its 
full stroke, and as it has now traveled further 
than it did in service position, the slide valve 
has also been moved a correspondingly greater 
distance on its seat, which brings a big slot, or in 
some triples, a removed corner (not shown) in 
the slide valve over a port in the seat (indicated 
by dotted lines behind port Z), and allows the 
auxiliary pressure to fall on the emergency pis- 
ton (8), which strikes the stem of valve 10 and 
forces it from its seat (which is kept closed by 
spring 12 and the trainpipe pressure in Y), and 
valve 10 being thus unseated, the air from Y 
rushes into the brake cylinder. 

As all this is done so very quickly that the 
trainpipe pressure has as yet reduced but very 
little, the remaining trainpipe pressure forces 
the check valve up and also rushes into the 
brake cylinder until it equalizes with what is left 
in the trainpipe, when spring 12 reseats the 
check valve, preventing the air in the brake 
cylinder from flowing back into the trainpipe. 

At the same time that the big slot in the back 
of the slide valve reached its position over the 



ITS USE AND ABUSE 63 

port in the seat leading to the emergency piston, 
another small port in the slide valve, marked S 
in plate 4, is placed in register with port r in the 
valve seat, taking the place of port Z, which 
allows the auxiliary pressure to flow into the 
brake cylinder on top of what went in from the 
trainpipe. 

The opening around the emergency valve is so 
much larger than port S in the slide valve that 
virtually no air enters the brake cylinder from 
the auxiliary until the check valve closes on the 
charge received from the trainpipe. 

It is this air from the trainpipe that gives the 
added twenty per cent brake power after an 
emergency application; for the air which enters 
the brake cylinder from the trainpipe has the 
same effect as shortening the piston travel, 
because it forces the auxiliary pressure to equal- 
ize just that much higher than it would if the 
brake cylinder was empty when the auxiliary 
pressure started to flow into it. 

On account of the trainpipe pressure having 
two outlets (one by way of the brake valve, and 
the other by way of valve 10) when an emer- 
gency application is made, it is reduced so sud- 
denly that the next triple is thrown into quick 
action, because the pressure that was holding 



64 MODERN AIR-BRAKE PRACTICE 



TO auxiuahv nescnvoii 




PLATE NO. 6 — PLAIN TRIPLE VALVE. (OLD STYLE.) 



ITS USE AND ABUSE 



^S 



DESCRIPTION OF PLATE 6 — PLAIN TRIPLE VALVE, 
RELEASE POSITION (OLD STYLE) 

W. Trainpipe connection. 

X. Cylinder connection. 

Y. Auxiliary reservoir connection. 
15. Handle of cut-out plug 13. 
18. Slide valve. 

5. Triple piston. 

7. Graduating valve. 

8. Graduating stem. 

9. Graduating spring. 



66 MODERN AIR-BRAKE PRACTICE 

that triple to release position immediately rushes 
back into the empty space just created in the 
trainpipe by the first reduction, and as it can't 
be in both places at the same time, the triple is 
left without sufficient trainpipe pressure to hold 
it, when the pressure on the auxiliary side of 
that triple piston drives it to emergency position, 
which in turn creates a vacancy in the train- 
pipe on that car which the next car tries to fill, 
and so on, till all the brakes on the entire train 
are set in emergency, and it ail happens so quick 
that the triples on a train of fifty cars can be 
thrown into quick action in about two seconds. 

PLATE 6 — PLAIN TRIPLE, OLD STYLE 

This plate illustrates the common form of 
plain triple, and before the advent of the quick- 
action triple, it was the standard for passenger 
cars. It is now mainly used on driver and ten- 
der brakes having cylinders of ten inches, or 
less; but with larger cylinders the new plain 
triple, as shown in plate i, is used. 

The principal difference between these two 
kinds of plain triples is the arrangement of the 
cut-out cock. In plate 6 you will notice that the 
cut-out cock is attached right to the triple, and 
by turning the handle, which controls plug 13, 



ITS USE AND ABUSE 67 

you can make the triple work "automatic" by 
placing it horizontal, and to cut it out place it at 
an angle of forty-five degrees; to make it work 
"straight air" place the handle perpendicular, for 
then plug 13 is turned so that the end of the 
passage which is shown to be in register with 
port d, would then be in register with port «, 
and the other end of e would register with dy 
which would allow trainpipe pressure to flow 
direct into the brake cylinder through ports a^ 
e and d\ in other words, the triple valve proper 
and auxiliary reservoir would not be used when 
the handle was turned for "straight air." This 
is so seldom done nowadays that there is a lug 
cast on the handles of all such plain triples to 
prevent cutting them in straight air. 

When it becomes necessary to bleed off a 
brake that is set with a plain triple, you must 
drain the auxiliary before closing the cut-out 
cock, for, when cut out, the position of the pas- 
sage is changed so that the air in the brake 
cylinder cannot escape through the triple 
exhaust. 

With the new plain triple, plate i, the cut-out 
cock is on the pipe leading from the triple to the 
brake cylinder. By this arrangement it is pos- 
sible to keep the driver brakes temporarily set 



68 MODERN AIR-BRAKE PRACTICE 

on descending mountain grades, until the aux- 
iliary is fully recharged, by simply setting the 
brakes and then cutting the driver brakes out 
before releasing. You can keep the driver 
brakes set while the train brakes are being 
released, by cutting out the driver brakes just 
before releasing. 

In the new plain triple the ports are neces- 
sarily larger, on account of handling a greater 
volume of air. 

PLATE 7 — TRIPLE VALVE, AUXILIARY RESERVOIR 
AND BRAKE CYLINDER COMBINED 

This plate illustrates a freight equipment. 
The brake cylinder (2) is bolted directly to the 
auxiliary reservoir (10), and while the supply 
pipe (d) runs through the auxiliary and into the 
cylinder, still the air in the auxiliary cannot get 
into the cylinder except by way of the ports in 
the triple, as previously described, for the left 
end of pipe d is connected with the triple at C, 
as shown in plate 4. 

The gasket between the auxiliary and brake 
cylinder is not for the purpose of separating 
them, but is to make the cylinder air-tight at 
that end, and when the brakes are set the other 
end of the cylinder is made air-tight by the 



ITS USE AND ABUSE ^Q 

packing leather (7) around the piston head (3), 
which is held to its place by the expansion ring 
(8) and follower (6). Spring 6 is to force the pis- 
ton back when the air is let out of the cylinder. 

To prevent the brakes from setting on account 
of trainpipe leaks, there is a small leakage 
groove (a) cut in the wall of the cylinder for 
about three inches from the extreme left end, or 
pressure head, so that any small amount of air 
that might be let into the cylinder through the 
triple, from any cause, would escape to the 
atmosphere, instead of pushing the piston out, 
by passing through the leakage groove by the 
piston head, and out around piston 3. 

TAe Release Valve (17) or 'bleeder," is for the 
purpose of drawing the air from the auxiliary, 
and when a car is set out, and especially when a 
brake is cut out, the release valve should be held 
open until all the air in the auxiliary has escaped, 
for if any air is left in it the brake will again set 
whenever the trainpipe pressure is reduced 
lower than that in the auxiliary. Whenever a 
brake cannot be released from the engine, but 
has to be "bled off," either at the auxiliary, or 
by the release signal valve on top of the car, 
always cut that brake out at the first opportunity 
and drain the auxiliary. 



70 MODERN AIR-BRAKE PRACTICE 




PLATE 7. TRIPLE VALVE, AUXILIARY RESERVOIR AND BRAKE 

CYLINDER COMBINED. 



ITS USE AND ABUSE 71 



DESCRIPTION OF PLATE 7 — TRIPLE VALVE, AUX- 
ILIARY RESERVOIR AND BRAKE 
CYLINDER COMBINED 

2. Brake cylinder. 

3. Brake piston. 

4. Non-pressure head of brake cylinder. 
6. Follower. 

7% Packing leather. 

8. Expansion ring. 

9. Release spring. 

10. Auxiliary reservoir. 

11. Drain plug. 

17. Release valve (or bleed cock). 

a. Leakage groove. 

b. Supply pipe, between triple and cylinder. 



72 MODERN AIR-BRAKE PRACTICE 

More money is paid out annually by railroad 
companies on account of freight wrecks caused 
by bleeding off ''stuck" brakes than would pay 
for a tolerably good railroad, for the reason that 
where a car is not equipped with a release sig- 
nal on top, and a brakeman bleeds the auxiliary 
as the train is pulling out and then climbs 
aboard, that brake is almost sure to stick again, 
while the train is moving too fast to allow the 
brakeman to get at the auxiliary bleed cock, and 
as a consequence the wheels are either flattened, 
draw-heads pulled out, train stalled, or the 
wheels become overheated, so that they burst 
and wreck the train. Where cars are equipped 
with the new release signal the brakeman can 
keep a brake off that is inclined to stick, until 
the train is in a safe position to allow him to get 
down and cut the brake out. 

If the auxiliary release valve leaks and it can- 
not be stopped by one or two quick jerks, to dis- 
lodge the dirt that is causing it to leak, cut the 
brake out, as no air can accumulate in the aux- 
iliary, thus making that brake worthless, but the 
leak is drawing air from the trainpipe, which 
affects the rest of the brakes. Should the 
release valve become clogged so that no air 
could be drawn through it, you can remove the 



ITS USE AND ABUSE 73 

drain plug (11) in the under side of the auxiliary. 
This plug will not have to be removed, of course, 
where a car is equipped with the release signal 
as the brake cylinder can be emptied independ- 
ent of the action of the triple, by simply pressing 
down on the valve of the release signal. 

PLATE 8 — PRESSURE-RETAINING VALVE 

Many enginemen and trainmen utterly fail to 
realize the importance of this little device, and 
in view of the wonderful aid it is to handling 
trains down heavy grades, it is surprising that, 
by the average man, it is less understood than 
almost any part of the equipment. 

A true story is told of an engineer who had 
just made a stop at the foot of a heavy grade on 
which the brakeman had turned up a few 
"retainers," and just as he was about to pull out, 
the brakeman asked if he should turn the 
retainers down, when the engineer "hollered" 
back, "No, you needn't mind, I can kick 'em off 
with my brake valve." 

Now let us see if he could kick them off. In 
the first place a retaining valve, as the name 
implies, is for the purpose of retaining a certain 
amount of pressure in the brake cylinder after 
the triple valve has been moved to release posi- 



74 MODERN AIR-BRAKE PRACTICE 

tion. It is simply a cork for the triple exhaust, 
and when you look at plate 8 you will readily 
understand this. 

Into the triple exhaust a small pipe is attached 
and extends from the triple to the top of the car 
at the end where the hand-brake staff is, and 
onto this pipe is attached the retaining valve at 
the connection marked X.. The handle (5) con- 
trols a plug (6) similar to the cut-out plug (13) in 
the plain triple. When the handle is turned as 
you see it in plate 8, port c through the plug is 
in register with port b-b, and the air which 
comes from the triple exhaust is forced against 
the seat of the valve 4, which raises and allows 
the pressure to escape to the atmosphere 
through port d. As port d is controlled by 
valve 4, the air will exhaust only while this 
valve is up, and as the weight of the valve, com- 
bined with the size of the parts, requires a pres- 
sure of fifteen pounds to keep it up, just as soon 
as the pressure in the brake cylinder has been 
reduced to a fraction less than fifteen pounds to 
the square inch, the valve will seat and retain 
the remaining pressure in the brake cylinder 
until the handle is turned down. When the 
handle is turned down it brings port a in register 
with the lower part of b, and port c is turned to 



ITS USE AND ABUSE 



75 




PLATE NO. 8. — PE.ESSUEE-RETAINING VALVE. 



DESCRIPTION OF PLATE 8 — PRESSURE-RETAINING 
VALVE, IN RETAINING POSITION 



X. Triple exhaust connection. 

4. Retaining valve weight. 

5. Handle. 

6. Cut-out plug. 



76 MODERN AIR-BRAKE PRACTICE 

register with port e^ and thereby allows all the 
air in the brake cylinder to escape to the atmos- 
phere. 

Therefore if the handle of the retainer is kept 
turned down the engineer can release the brakes 
from the engine, but if the handle is turned up 
(unless the brake leaks off) it will stay set until 
the handle is turned down. 

Retainers were formerly made to hold only 
ten pounds in the brake cylinder, but are now 
made to hold fifteen. 

With the retainer handle turned up, the 
second application of the brakes will give a 
much higher brake - cylinder pressure, if the 
auxiliary has been allowed time enough to 
recharge, because the pressure that is already 
in the cylinder will force the auxiliary to equal- 
ize much higher than it would if the cylinder 
was empty to start with (in the same manner 
that the emergency application causes an added 
pressure on account of the trainpipe pressure 
entering the cylinder before the auxiliary pres- 
sure has a chance to get in). For this reason it 
is best to apply the brakes and recharge the 
auxiliaries as soon as possible after passing the 
summit of a mountain grade, and besides it 
gives an increased reserve of brake power. 



ITS USE AND ABUSE 77 

THE AUTOMATIC SLACK ADJUSTER 

The question of correct piston-travel is of the 
highest importance, and the automatic slack 
adjuster is for the purpose of keeping it as 
nearly uniform as possible, which should be 
eight inches when running. 

PLATE 9 — SLACK ADJUSTER COMPLETE 

Plate 9 shows how the adjuster is attached to 
the pressure head of the brake cylinder. One 
end of cylinder lever (5) is bolted to a cross 
head, which moves in a guide (4) that is bolted 
to the pressure head of the cylinder. The cross 
head is held to its place by a threaded rod (i), 
which has a ratchet nut where its opposite end 
extends through the adjuster body (3), and when 
it is desired to reduce the piston travel, it is done 
by moving the cross head away from the cylin- 
der head a distance equal to the amount of slack 
to be taken up; and to increase the travel move 
the cross head toward the cylinder. 

When no air is in the cylinder the threaded 
rod can be turned either way with a wrench, 
and four turns of the rod will equal one inch of 
piston travel. 

In running along,.whenever the piston travel 
exceeds eight inches the adjuster automatically 



78 MODERN AIR-BRAKE PRACTICE 




PLATE NO. 9 — AUTOMATIC SLACK ADJUSTER, COMPLETE 



ITS USE AND ABUSE 79 



DESCRIPTION OF PLATE 9 

5. Cylinder lever. 

1. Threaded rod. 

3. Ratchet-nut wheel casing. 

2. Adjuster cylinder. 

a and b. Pipe connection between brake cylin- 
der and adjuster cylinder. 



So MODERN AIR-BRAKE PRACTICE 




PLATE NO. 10. — AUTOMATIC SLACK ADJUSTER. 



ITS USE AND ABUSE 



DESCRIPTION OF PLATE ID 

27. Ratchet-nut wheel. 

22. Pawl. 

a. Projection for lifting pawl. 

23. Piston. 

21. Release spring. 



82 MODERN AIR-BRAKE PRACTICE 

takes up one thirty-second of an inch every time 
the brake is released, and therefore whenever 
new shoes are put on (which necessitates letting 
the adjuster well back), the brake should be fully 
applied and whatever travel the piston shows 
over 6>^ inches should be taken up by turning 
the ratchet nut, as the running piston travel is 
from one to two inches greater than it is when 
the car is standing still. 

Don't try to turn the ratchet nut while the 
brake is set, and never alter the dead levers or 
bottom rods unless, with all adjuster slack out, 
the piston-travel is less than 5>^ inches, or when 
the adjuster has been taken up to its limit and 
the travel is too long, and not then in the latter 
case if any brake shoes need renewing. 

Plate 10 illustrates the adjuster in cross sec- 
tion. 27 is the ratchet nut which is attached to 
the threaded rod; 22 is the pawl which moves 
the ratchet nut; 23 is the piston, to which the 
pawl is attached, and 21 is the spring which 
drives the piston back after the cylinder pres- 
sure has escaped from in front of it, and as the 
adjuster cylinder is connected to the brake 
cylinder by a small pipe, whenever the air in the 
brake cylinder forces the brake piston out eight 
inches, brake-cylinder pressure is admitted 



ITS USE AND ABUSE S;^ 

against piston 23, which forces the pawl back so 
that it engages the ratchet-nut wheel, and when 
the air is released from the brake cylinder the 
air in the adjuster cylinder (11) escapes through 
the non-pressure end of the brake cylinder, and 
spring 21 pushes the piston and pawl forward, 
thus turning the ratchet-nut wheel the distance 
of two teeth, which takes up one thirty-second 
of an inch of piston-travel. The pawl is released 
by striking a projection (a), which keeps it up. 

P/aU II illustrates the degree of angularity at 
which the port in the brake cylinder should be 
tapped according to the size of the cylinder. As 
this port is only one-eighth of an inch, it may 
easily become clogged, so that if the adjuster 
fails to work you should at once ascertain if the 
air passages are open between the brake and 
adjuster cylinders by loosening the union swivel 
on the adjuster cylinder connection. 

Whenever the adjuster has operated to the 
limit of the screw and the pawl fails to release, 
so that the ratchet-nut cannot be started back 
with a wrench, if it be the old style adjuster, 
remove the ratchet nut cover and carefully pry 
the piston outward until the pawl can be raised, 
then slack back the nut about a turn, which will 
let the piston return to the end of its cylinder 



84 



MODERN AIR-BRAKE PRACTICE 



PORT JO BE.sI-VrOM, PRESSURE HEAD. 




PLATE NO. 11.- 



-AUTOMATIC SLACK ADJUSTER — SIZE OF 
CYLINDER PORT. 



DESCRIPTION OF PLATE II 

The illustration shows the angularity at which 
the brake-cylinder port should be drilled for the 
different sized cylinders. 



ITS USE AND ABUSE 85 

and keep the pawl free from the ratchet nut as 
before. 

An improvement has lately been added by 
inserting a stop screw next to the ratchet-nut 
casing, which holds the threaded rod a short dis- 
tance from its extreme travel, so that in case the 
pawl sticks it is only necessary to back out the 
stop screw, when the pawl will release itself 
automatically. The adjuster cylinder should be 
cleaned and oiled every time the brake cylinder 
is oiled. 

PLATES 12 AND 1 3 — THE RELEASE SIGNAL 

As the high-speed brake and the automatic 
slack adjuster have both become necessary as 
the result of changed conditions in the operating 
of railroads, in like manner, owing to the great 
increase of railroad traffic and other conditions, 
the air-brake release signal has also become a 
necessity, when the saving of time, property and 
human life are taken into account. Railroads 
to-day are not only running very heavy trains, 
but are running many of them, and, on some 
roads, they are vastly too close together for the 
comfort of the train crews who have to operate 
them. As long as railroads are compelled to 
employ new men and as long as many of the 



86 



MODERN AIR-BRAKE PRACTICE 




PLATE 12 — THE RELEASE SIGNAL, SHOWING CONNECTION TO 
BRAKE CYLINDER, AND EDGE OF SIGNAL AS IT AP- 
PEARS ABOVE THE TOP OF BOX CAR, 
IN APPLICATION POSITION. 



ITS USE AND ABUSE 87 



DESCRIPTION OF PLATE 12 

The release signal is here shown edgewise. 

X. The brake-cylinder connection of signal 
pipe. 

B-B. The release-signal pipe. 

A. The release-signal cylinder (i" inside 
diameter.) 

E. The hollow piston-rod and release-signal 
staff. 

D. The metal signal (edgewise), i foot square. 

G. The release valve on end of the release- 
signal staff and piston-rod. 



88 



MODERN AIR-BRAKE PRACTICE 




PLATE NO. 13. — THE RELEASE SIGNAL IN RELEASE POSITION. 



ITS USE AND ABUSE 89 



DESCRIPTION OF PLATE 1 3 

The release signal is here shown in release 
position. 

B. Release-signal pipe leading to brake cyl- 
inder. 

C. I. Piston (i" diameter). 

C. 2. Return spring. 
A. Cylinder. 

E. Hollow piston-rod and signal staff. 

D. Metal signal (i foot square, perforated, on 
freight cars. On passenger coaches 4"x 6 "). 

G. Release valve. 

aa and Fig. 2a. — Triangular stem of release 
valve. 

bb and Fig. 2b. Triangular shape of piston-rod 
to prevent turning. 

CC. Piston-rod hood, to prevent water from 
getting into cylinder. There is also a hood over 
the release valve for the same purpose. 



90 MODERN AIR-BRAKE PRACTICE 

older employes continue to be indifferent to the 
proper care, maintenance and operation of 
the air-brake equipment, just so long will we 
continue to have dangerous delays to trains, 
damage to merchandise and rolling stock, and 
frequent taking of human life, as the direct 
result of bad handling or bad condition of the 
air brakes. 

The question of keeping the brakes in good 
order is a continually growing trouble, and to 
know for a certainty that they are in good con- 
dition is of vital importance. 

The new device which is meant to largely 
overcome these distressing conditions is known 
as the release signal, shown in plates No. 12 
and No. 13. 

As the automatic reducing valve of the high 
speed brake is attached to the brake cylinder 
and as the automatic slack adjuster is also oper^ 
ated by brake-cylinder pressure, in like manner 
the release signal is also connected to the brake 
cylinder, so that whenever there is air in the 
brake cylinder that fact is instantly made known 
by the release signal. 

The release signal is composed of a cylinder 
in which is contained a piston, piston-rod and 
return spring, being in reality a miniature of the 



ITS USE AND ABUSE 91 

brake cylinder, with this difference: the piston- 
rod extends up far enough to allow a square 
metal signal to be fastened to it, so that when- 
ever the brake-cylinder pressure causes the 
brake to apply, the same pressure forces the 
release signal piston up, so that the metal signal 
is brought to full view of the trainmen and 
enginemen alike, thereby signaling them that 
the brake on that car is set. When the en- 
gineer releases the brake and the brake cylin- 
der is empty, there is then no pressure under 
the release signal piston, and the return spring 
forces the metal signal down out of sight. 
Should the engineer be testing brakes, and, 
while the brakes were being held on, if the 
release signal should be seen to gradually drop, 
it would mean that the brake on that car was in 
bad order, for the signal would not go down 
unless the air was escaping from the brake cylin- 
der. Should a signal be seen to drop and no air 
was found to be coming out through the retain- 
ing valve, it would mean that the brake was 
''leaking" off, but if the signal dropped and at 
the same time air was heard to be escaping 
through the retainer, it would mean that the 
brake was "releasing" through the triple. This 
point is very important to remember, for if a 



Q2 MODERN AIR-BRAKE PRACTICE 

brake "releases" when it should stay set, the 
triple valve, or auxiliary gasket, or auxiliary 
release valve needs attention. But, if a brake 
"leaks" off, the packing leather in the brake 
cylinder needs oiling. Therefore, if you report 
a defective brake as having leaked off, the 
repairman will know at once what to do and 
thereby save considerable time. 

Should the signal remain up after the engineer 
has released the rest of the brakes, it means that 
the triple on that car is unfit for service, and 
should this happen while the train is in motion 
serious trouble is likely to follow. But, as the 
piston-rod and signal staff of the release signal 
is made of a single piece of pipe, and as there is 
a valve on the end of it, the brakeman can, by 
simply pressing down the valve, drain the brake 
cylinder independently of the action of the triple 
without stopping the train and without getting 
off. 

Should a brake have too much piston-travel 
the release signal will indicate it, for with the 
proper piston-travel and an auxiliary pressure 
of seventy pounds, a ten-pound trainpipe reduc- 
tion will cause the signal to go to its full stroke, 
but the same reduction with too much piston- 
travel will cause the signal to stop at half-mast. 



ITS USE AND ABUSE 93 

This stopping at half-mast is caused by reason 
of the tension of the return spring, combined 
with the lowered pressure in the brake cylinder. 

The release signal is located on freight cars on 
the end opposite to that on which is located the 
hand-brake staff, near the ladder, just below the 
top of the car. There is a metallic casing into 
which the signal drops when no air is in the 
brake cylinder, but every time the brake sets the 
signal is raised above the top of the car, so that 
it can be seen from either end of the train, or 
from the ground. For instance, when the brakes 
are being tested at terminal points, or when any 
change has been miade in the make-up of the 
train by setting out or picking up cars, the action 
of the release signal will notify every one alike 
just what condition the brakes are in. The 
holes in the metal signal are to allow a free pas- 
sage of wind, so that it cannot be blown off in a 
gale. The cup-shaped hoods on the signal staff 
and top of the release valve are for the purpose 
of preventing any water getting into the signal 
cylinder and also to avoid freezing up. 

The release signal needs no more attention 
than is ordinarily given to the retaining valve, 
as it is so simple in construction that it is almost 
impossible for it to get out of order. It needs 



94 MODERN AIR-BRAKE PRACTICE 

no oiling, as the oil from the brake cylinder is 
sufficient to care for the one-inch piston in the 
release signal cylinder. 

On flat and coal cars the release signal is 
attached to both ends of the car, so that it 
shoots out from the sides of the car. In pas- 
senger service it is located on the inside by the 
door at each end of the car, so that it can be seen 
by the trainmen in whatever direction they may 
be passing through the train. On locomotives 
it is placed in easy reach, so that when the 
tender brake sticks it can be let off before any 
damage is done. On freight cars the metal sig- 
nal of the release signal is a foot square, so that 
it can be easily seen by the trainman on a dark 
night by the light of his lantern, as he passes 
over the train. When a brake sticks and cannot 
be released from the engine, it is only necessary 
to hold down the valve on the end of the signal- 
staff a few seconds to drain the brake cylinder, 
when the release signal will automatically drop 
back into its pocket. 

THE conductor's VALVE 

What is known as the conductor's valve is 
merely an additional stop cock attached to the 
trainpipe of passenger coaches. 



ITS USE AND ABUSE 95 

There is a branch pipe running from the train- 
pipe up through the body of the coach, usually in 
the toilet room, and on this branch pipe is a stop 
cock, or valve, so that in case the conductor is 
unable to signal the engineer, or an emergency 
arises making it necessary to stop the train as 
quick as possible, the conductor can let the air 
out of the trainpipe by simply opening this 
valve. 

If he wishes to make a gradual stop he has 
only to open the valve gradually, but if he 
wishes to stop quick, he must open the valve 
quick, and also must hold it open until the train 
is stopped, for if the engineer should fail to lap 
his brake valve, as soon as the conductor's valve 
was closed the brakes would release, on account 
of the main reservoir pressure driving the triples 
Lo release position. 

Having explained the construction and action 
of the plain and quick-action triple valves, the 
pressure-retaining valve, the slack adjuster, the 
release signal and the conductor's valve and 
shown how these parts, together with the aux- 
iliary and brake cylinder, are combined to form 
the car equipment, now let us see by what means 
the air is compressed, where it is stored and how 



96 MODERN AIR-BRAKE PRACTICE 

it is manipulated from the engine. This brings 
us to 

PLATE 14 — THE EIGHT-INCH PUMP 

The eight-inch pump is so called on account 
of the bore of the cylinders being eight inches. 
It has two cylinders, the one on top (3) is the 
steam cylinder, and the one below (5) is the air 
cylinder. They are joined together by a neck (4), 
and in the top of the air cylinder and bottom of 
the steam cylinder there are stuffing boxes (56) 
through which passes a piston-rod, on each end 
of which there are piston heads (12 and 13). 
The piston-rod (10) is hollow for a sufficient 
depth to admit the stem (17) of the reversing 
valve (16). The reversing plate (18) is bolted on 
top of steam piston (10) so that it strikes the 
button on the stem 17 as the piston approaches 
the end of its down stroke, and strikes the 
shoulder of the stem 17 as it makes the up 
stroke, for the purpose of changing the position 
of the reversing valve (16), which reverses the 
stroke of the pump. 

The valves through which the air is received 
and discharged are all in the lower, or air end 
of the pump. 

The Action of the Steam End of the Pump is as 



ITS USE AND ABUSE g; 

follows: Steam from the boiler enters the pump 
at the union swivel 54, and besides filling the 
chamber which contains the main valve (7), 
passes through a port in the wall of this cham- 
ber and through a passage (not shown in plate 14) 
to the chamber in which the reversing valve 
works, thereby constituting the main valve 
chamber and the reversing valve chamber as 
the two steam chests of the pump. 

From the reversing valve chamber the steam 
passes through a small port into the space occu- 
pied by the reversing piston (23), as shown in 
plate 14, and as the combined area of piston 23 
and small piston 9 is greater than the area of the 
large piston 8, the main valve (7) is forced down 
until the small piston strikes the stop pin (50) 
and thus uncovers the port in bushing 26, which 
admits steam to the underside of main piston 10, 
forcing it up. 

As the main piston moves up, plate 18 strikes 
the shoulder of stem 17 and thus changes the 
position of the. reversing valve, so that the top 
port in its chamber is closed to piston 23, and 
the two lower ports are connected by the cavity 
in the reversing valve, which allows the steam 
to flow from off the top of piston 23, and pass 
under it into the exhaust passage across the 



98 



MODERN AIR-BRAKE PRACTICE 




PLATE 14 — EIGHT-INCH PUMP. 



ITS USE AND ABUSE 99 



DESCRIPTION OF PLATE 1 4 — EIGHT-INCH PUMP, ON 
THE UP-STROKE 

54. Boiler connection. 

7. Main valve. 

y-^ and 7-9. Large and small piston of main 
valve. 

25 and 26. Main valve bushings. 

50. Stop pin. 

23. Reversing piston. 

16. Reversing valve. 

17. Reversing valve stem. 

18. Reversing plate. 

10 and II. Main steam and air pistons. 

3. Steam cylinder. 

4. Neck. 

5. Air cylinder. 

57. Main steam exhaust. 
41. Drain cock. 

30 and 32. Discharge valves. 

31 and 33. Receiving valves. 
53. Main reservoir connection. 



LofC. 



lOO MODERN AIR-BRAKE PRACTICE 

head, as shown by dotted lines, to the main 
exhaust. When the pressure is thus shut off 
from piston 23, the main valve raises and causes 
the small piston to close the steam port to the 
underside of the main piston, and opens the 
exhaust port leading into the passage in the bot- 
tom of the cylinder, shown by dotted lines, and 
out at the main exhaust, at the same time pis- 
ton 8 of the main valve closes the top exhaust 
port in bushing 25 and opens the supply 
port through the bushing, and thus admits 
steam on top of the main piston, which drives it 
down. 

In making the down-stroke, plate 18 engages 
the button on stem 17 and again changes the 
position of the reversing valve, which again 
admits steam on top of the reversing piston, 
which causes the main valve to move down as 
before, and piston 8 uncovers a port in the bush- 
ing 25 which exhausts the steam from off the top 
of the main piston, and at the same time piston 
9 opens the supply port in bushing 26, which 
admits steam to the underside of the main pis- 
ton, and at the same time closes the lower 
exhaust. The pump has now made a complete 
double stroke. 

Drain cock 41 must always be opened before 



ITS USE AND ABUSE loi 

the pump is started, and left open until the pump 
is warmed up, or until there is about thirty 
pounds pressure in the main reservoir, and great 
care must be taken to start the pump slow, to 
avoid pounding and jarring, as the condensation 
cannot be compressed, and there must be an air 
cushion for the piston head to strike against in 
the lower cylinder. 

The Action of the Air End of the Pump is as 
follows: There are four air valves, two are 
called receiving valves (31 and 33), and two are 
called discharge valves (30 and 32). There are 
two valve cages (34 and 43), and as the discharge 
valves have a greater area than the receiving 
valves, in the eight-inch pump, the flow of air 
past the valves is determined by the lift each 
valve has; the receiving valves have a lift of 
one-eighth of an inch, while the discharge valves 
have a lift of three thirty-seconds of an inch, 
or one-thirty-second less than the receiving 
valves. 

These standards must never be changed, as 
too much lift of any of the valves will cause the 
pump to pound, and not enough lift will cause it 
to run hot. 

The way in which the pump receives and dis- 
charges air is as follows: When piston 11 is 



102 MODERN AIR-BRAKE PRACTICE 

drawn up by steam piston lo there is a partial 
vacuum formed in the air cylinder beneath pis- 
ton II, and as the atmospheric pressure is about 
fifteen pounds to the square inch, the receiving 
valve 33 is forced off its seat by the air rushing 
in to fill up the space created by the partial 
vacuum, and if the piston was to stop when it 
reached the top, the valve would be seated by 
its own weight when the pressure inside and out 
of the cylinder equalized; but as the piston 
reverses just as it reaches the top, the valve is 
forced to its seat and held there by the compres- 
sion of the air on top of it, and if the valve has 
too much lift the pound heard when the valve is 
seated is great in proportion. 

When the piston starts on the down-stroke it 
compresses the air higher and higher as it 
nears the bottom, and when the pressure in the 
pump becomes greater than that in the main 
reservoir, the lower discharge valve (32) is forced 
up and the air from the pump rushes into the 
main reservoir, until the valve is seated by the 
main reservoir pressure becoming greater than 
that in the pump. 

The action of the top receiving and discharge 
valves is the same as the lower ones, except on 
the opposite stroke. 



ITS USE AND ABUSE 103 

PLATE 15 — THE NINE AND ONE-HALF INCH PUMP 

The Qj^-inch pump differs from the 8-inch 
pump in several ways. In the first place it is 
larger by lyi inches in the bore; second, the 
valve motion of the steam end is all contained 
in the top head, except the reversing valve stem, 
which is the same as in the 8-inch pump; third, 
the air valves are all the same size, and all have 
the same lift of three thirty-seconds of an inch, 
and the valves are placed so that the discharge 
valves are both on one side, and the receiving 
valves on the opposite side of the air cylinder; 
fourth, there is but one air inlet for the receiving 
valves, making it possible to strain all the air 
through one strainer, as indicated by 106, Fig. i. 
The main piston is the same in construction as 
in the 8-inch pump; there are two heads (67) on 
one piston rod (65), and this rod is hollow to 
admit the stem (71) of the reversing valve (72), 
and the reversing valve stem is driven up or 
pulled down by the reversing plate (69) striking 
the shoulder (/) or the button (70), just as it does 
in the 8-inch pump. 

As the reversing valve was the channel 
through which the steam had to pass to and 
from the top of the reversing piston in the 8-inch 
pump, in like manner the reversing valve in the 



I04 MODERN AIR-BRAKE PRACTICE 



NINE AND ONE-HALF INCH AIR PUMP. 




64 



116 



PLATE NO. 15. — NINE AND ONE-HALF INCH PUMP. 



ITS USE AND ABUSE 



105 



DESCRIPTION OF PLATE 1 5 — NINE AND ONE-HALF 

INCH PUMP 

94. Boiler connection, showing by dotted lines 
how steam passes to main-valve cham- 
ber A. Main steam exhaust is indicated 
by dotted lines and figures 61-92. 

^"j. Large piston of main valve. 

79. Small piston of main valve. 

83. Slide valve. 

105. Drain cock. 

71. Reversing-valve stem. 
69. Reversing plate. 

97. Stuffing boxes. 

98. Oil cup. 

65 and 67. Main steam and air pistons. 

106. Air inlet. 
86. Air valves. 

92. To main reservoir. 

75. Fig. 3. Main valve bushing. 

72. Fig. 2. Reversing valve. 



io6 MODERN AIR-BRAKE PRACTICE 

9>^-inch pump controls the flow of steam to and 
from the plain side of piston ']'] of the main 
valve, which in connection with the slide valve 
(83) controls the supply and exhaust ports in the 
steam cylinder. 

To explain this it is necessary to use two sec- 
tional views of the pump, as shown in plate 15. 
In Fig. I the pipe connection 93 shows by dotted 
lines how the steam from the boiler is carried 
through a passage in the back of the pump to 
the main-valve chamber. 

The main valve is composed of two pistons of 
unequal diameters, fastened to a suitable rod 
(76), and on this rod there are two shoulders 
between which a common D slide valve {^'^ is 
held. Fig. 3 represents the bushing in which 
the main valve and slide valve works. 

The slide-valve seat has three openings: the 
one on the left, in Fig. i, leads to and from 
the underside of the main piston; the one on 
the right leads to and from the top side of the 
main piston, and the one in the middle leads to 
the main exhaust, 92. Consequently when 
steam enters the main-valve chamber the piston 
']']y having the largest area, is forced to the 
extreme right, as in Fig. i, against the head 84, 
which causes the slide valve to uncover a port 



ITS USE AND ABUSE 107 

in the seat so that the steam can pass from the 
main-valve chamber down through a passage in 
the side of the cylinder to the underside of the 
main piston, which forces it up, and the revers- 
ing plate strikes the shoulder,/, on the reversing- 
valve stem, which drives the reversing valve up 
and allows the steam in the reversing-valve 
chamber to pass through the lower horizontal 
port in the main-valve bushing (see Fig. 3) into 
the chamber between the head 84 and piston ^"j. 
As this balances the pressure on both sides of 
the large piston ']'], the small piston 79 now pulls 
the slide valve to the opposite end of the cham- 
ber, which uncovers the supply port to the top of 
the main piston and allows the steam to force it 
down, and at the same time the steam from the 
underside is being exhausted by way of the 
cavity in the slide valve, which now has the 
lower supply port and the main exhaust con- 
nected. 

The reason the small piston pulls the large 
piston over, after the pressure is balanced on 
both sides of piston ^^, is because there is a 
small port between the plain side of piston 79 
and the head 85, which is always open to the 
main exhaust, so that no back pressure can 
remain in the chamber indicated by 82, and no 



io8 MODERN AIR-BRAKE PRACTICE 

partial vacuum can be formed on that side of the 
small piston. 

The main-valve chamber is always in com- 
munication with the reversing-valve chamber by 
a small port in the bushing (75), as shown in 
Fig. 2; cap nut 74 has a small port in it which 
allows live steam to always reach the top of the 
reversing-valve stem, for the purpose of keeping 
the pressure balanced on both ends of it. 

As the main piston is now making its down- 
stroke the reversing plate (69) engages the but- 
ton on the end of the reversing-valve stem and 
draws the reversing valve down to the position 
shown in Fig. 2, which connects the second hori- 
zontal port in the bushing with the port which in 
Fig. 3 appears to be vertical and having a short 
extension to the right, and as this port is always 
open to the main exhaust, the steam between 
piston ']^ and the head 84 is exhausted, which 
allows the steam in the main-valve chamber to 
again force piston 'j^ to the position shown in 
Fig. I, which places the slide valve in position to 
allow the steam to exhaust from the top of the 
main piston, and at the same time connects the 
main -valve chamber with the underside of 
the main piston, causing it to be forced up, as 
before. 



ITS USE AND ABUSE 109 

Like the eight-inch pump, the stuffing boxes 
(95) must be kept well packed, and the gland 
nuts (q6) just tight enough to stop leaks, but not 
tight enough to cause groaning. With metallic 
packing the nuts can be tightened more than 
they could if a fiber packing is used, for if you 
screw down too tight on a fiber packing it will 
ruin it. 

The drain cock (105) must be handled in the 
same way as the one on the eight-inch pump, 
but in addition to this one there is one in the 
main exhaust (not shown in Fig. i), and it also 
must be opened when starting the pump. 

THE ELEVEN-INCH PUMP 

The Westinghouse Air-Brake Company are 
now making an eleven-inch pump after the same 
pattern as the 9>^-inch one. 

As the 9>^-inch pump can compress about a 
third more air in a given time than the 8-inch 
pump, in like manner the ii-inch pump can 
compress a third more air than the 9>^-inch 
pump can within the same length of time. 

Right and Left Hand Pumps are pumps having 
two sets of plugs on either side of the steam 
cylinder, so that the pump can be located on 
either side of the engine as desired. All 9>^- 



no MODERN AIR-BRAKE PRACTICE 

inch and ii-inch pumps are now made right and 
left. 

To change a pump from right to left, or vice 
versa, remove the steam port fittings and oppo- 
site plug and exchange them, remove the 
exhaust port fitting and its opposite plug and 
exchange them. 

In oiling €\\h.^r the 8, 9^4 or ii-inch pump the 
steam end is oiled by a lubricator, and when first 
starting the pump, the oil should be allowed to 
flow at the rate of about fifteen drops a minute, 
but as soon as the pump is nicely warmed up, or 
say about thirty pounds pressure in the main 
reservoir, then the oil should be cut down to 
about one drop a minute^ if that will keep the 
pump lubricated so that it won't groan. Some 
pumps require more oil than others, according 
to the work they have to do. Too much oil in 
either end of the pump is ruinous. 

The air cylinder should be oiled regularly with 
good valve oil, as the old practice of oiling it 
only when the pump groans is now found to be 
bad practice. A good fat swab should always 
be kept on the piston-rod, and kept well oiled, 
which will help keep the air cylinder lubricated. 

Under no circumstances must oil be sucked in 
through the air inlet, as it will surely ruin the 



ITS USE AND ABUSE m 

pump. Whenever the air cylinder is to be oiled, 
the pump should be throttled down to a very 
slow speed, and after first filling the oil cup, 
watch the stroke of the piston, and, while it is 
going down, quickly open the oil cup and allow 
the oil to be sucked in before the piston starts 
up. This causes the oil to be sprayed around 
the cylinder. If oil was poured in while the 
pump was cold, just as soon as it was started up 
the oil would be forced into the main reservoir, 
and eventually find its way to the brake valve, 
and gum up the rotary, feed valve and pump 
governor. 

Some engineers say they can't oil a pump on 
the down-stroke for the reason that the oil blows 
back in their face; this is true only when the 
piston packing rings are leaky, and if the oil 
does blow back on the down-stroke, it tells you 
very plainly that new packing rings are needed, 
and needed bad, as one of the most common 
causes for the pump running hot is leaky pack- 
ing rings. A leaky discharge valve might cause 
a back blow, but if the pump is completely 
stopped and you hold your finger slightly above 
the open oil cup you can tell if the trouble is 
there. 

Never Use Anything but Good Valve Oil for 



112 MODERN AIR-BRAKE PRACTICE 

either end of the pump, as the heat generated 
by the compression of air is so great that it 
requires oil of a high flashing point to withstand 
it. On a warm summer s day the air in a pump 
working against a ninety-pound pressure in the 
main reservoir is about 550 degrees, and on a 
cold winter's day, when the thermometer is thirty 
degrees below freezing, the pump generates a 
heat of 300 degrees against a ninety-pound main- 
reservoir pressure. And if you run your pump 
faster than sixty or seventy full strokes a min- 
ute, or have leaky packing rings or leaky dis- 
charge valves, the heat is raised considerably 
higher. 

The air valves in the 9>^-inch pump operate 
the same as in the 8-inch. But the lift of the 
the air valves in the 9>^-inch pump are all the 
same, whereas they differ in the 8-inch pump, as 
previously explained. 

PLATE 16 — PUMP GOVERNOR 

When an engine is equipped with a brake 
valve on which there is a feed valve attachment, 
the pump governor controls the main-reservoir 
pressure. 

But when the D-8 brake valve is used, the 
governor controls the trainpipe pressure. 



ITS USE AND ABUSE ' 113 

While the new style governor is very similar 
to the old style, the new one is much more reli- 
able, as it is more positive in its action. 

The governor is located on the steam p.pe 
leading to the pump, as its purpose is to shut off 
the steam whenever the pump has compressed 
the required amount of air, and whenever the 
air pressure falls below standard, the governor 
automatically reopens the valve in the steam 
pipe and keeps it open until the air pressure is 
again restored, when it again shuts off the 
steam. 

This action is very simple. As the steam 
enters the governor at x, it passes under the 
steam valve (51) and through Y into the pump, 
and as long as the steam valve is unseated the 
pump will continue to work and compress air 
right up to boiler pressure; but as ninety pounds 
is all that is wanted in the main reservoir with 
the regular quick-action equipment, the tension 
spring of the governor must be set so that the 
steam valve will seat when ninety pounds is 
reached. 

This is done as follows: you will notice that 
piston 53 rests on the stem of the steam valve, 
and that the area of piston 53 is several times 
greater than the area of the steam valve, which 



114 MODERN AIR-BRAKE PRACTICE 




To Main BeieiTotr 
Connectloa 26 on 
lingineer'i Brake 
Valve. ^ 




PLATE NO. 16. — PUMP GOVERNOR. 



ITS USE AND ABUSE 115 



DESCRIPTION OF PLATE 1 6 — PUMP GOVERNOR 

X. Boiler connection. 

Y. To pump. 

51. Steam valve. 

53. Air valve. 

56. Air-valve spring. 

62. Vent port. 

67. Diaphram and valve. 

68. Diaphram ring. 
66. Regulating spring. 
65. Regulating nut. 
W. Main reservoir. 
61. Waste-pipe stud. 



ii6 MODERN AIR-BRAKE PRACTICE 

means that if the relative areas were as three is 
to one that when a fraction over fifty pounds of 
air got on top of piston 53 it would drive the 
steam valve to its seat against a steam pressure 
of 150 pounds. 

The manner in which the air is admitted to 
the top of piston 53 to stop the pump, or kept 
from it to allow the pump to run, is as follows: 
A small pipe leading from the main-reservoir 
return pipe is connected to the governor at W, 
which allows main-reservoir pressure to always 
fill the chamber under diaphram 67, and as this 
diaphram is held down by a tension spring (66) 
and as there is a small pin valve attached to the 
center of the diaphram which closes the port 
leading to the top of piston 53, whenever the air 
pressure becomes greater under the diaphram 
than the tension of the spring, it will cause it to 
raise and unseat the pin valve, and allow the air 
to reach the top of piston 53, causing it to seat 
the steam valve and stop the pump. If the ten- 
sion spring 66 is properly set the pump will stop 
when there is ninety pounds in the main reser- 
voir. Whenever the main-reservoir pressure 
gets lower than the tension of the spring, the 
diaphram valve drops back to its seat and the 
air escapes from the top of piston 53 through a 



ITS USE AND ABUSE n; 

small vent port (62) which allows spring 56 to 
aid the steam in lifting the steam valve from its 
seat. 

If the vent port 62 is not kept open the pump 
will be slow in starting, for the air could only get 
off the top of piston 53 by passing down around 
packing ring 54 and out at the waste-pipe con- 
nection {£■)', Stud 60 is tapped in the back of the 
governor under piston 53, to carry off any steam 
that might leak by the stem of valve 51, or any 
air that might leak around packing ring 54, con- 
sequently should both the vent port and the 
waste pipe become clogged the governor would 
not shut off the pump, and the main-reservoir 
pressure would run up to boiler pressure. 

PLATES 17 AND 1 8 — D-8 ENGINEER'S BRAKE VALVE 

In applying the brakes with the quick-action 
triple, it is not only necessary to reduce the train- 
pipe pressure lower than that in the auxiliary, 
but it is absolutely necessary that the reduction 
be made gradually to prevent the emergency 
action. 

The old style brake valve, or three-way cock, 
had only three positions, application, lap and 
release, and while some men seem to think the 
new brake valve has only two positions, "on" and 



ii8 MODERN AIR-BRAKE PRACTICE 



f [ mill 

^ -, — Ui 




PLATE NO. 17.— D-8 BRAKE VALVE AND BOTAKT SEAT. 



ITS USE AND ABUSE 119 



DESCRIPTION OF PLATE 1 7 — D-8 BRAKE VALVE 

X. Main reservoir connection. 
R. Gauge connection for red hand. 
W. Gauge connection for black hand (or train- 
pipe). 
T. To the little drum. 
V. To the pump governor. 
Y. Trainpipe. 

17. Equalizing discharge valve. 

18. Rotary valve. 

22. Body gasket. Fig. 3 shows rotary seat 
and preliminary exhaust port h, and 
equalizing port^-, both lead into cavity/^. 



I20 MODERN AIR-BRAKE PRACTICE 

"off," there are, however, five positions, as fol- 
lows: full release, running position, lap, service 
application, and emergency. 

There are two kinds of brake valves, one has 
no feed-valve attachment, and is known as the 
D-8, and depends upon the pump governor to 
regulate the trainpipe pressure. The other 
kind has a feed-valve attachment for controlling 
the trainpipe pressure, which leaves the pump 
governor to control the main-reservoir pressure, 
and is known as the F-6 and G-6 brake valve, 
according to the kind of feed valve there is on 
it. The F-6 has the old style feed valve, and 
the G-6 has the new slide valve feed valve, as 
shown in plates 21 and 22. 

It is not necessary to go into details in describ- 
ing the D-8 brake valve, as it is now practically 
superseded by the F-6 and G-6, therefore I will 
simply explain the differences between the two 
kinds of brake valves, and will fully explain the 
F-6 under plates 20 and 21. 

The D-8 brake valve uses the pump governor 
to control the trainpipe pressure of seventy 
pounds, and the connection is made at V (plate 
17); the "excess" is controlled by what is known 
as the excess pressure valve (19, Fig. 3, of 
plate 17). 



ITS USE AND ABUSE 121 

When the handle of the D-8 brake valve is in 
full release position the pump will shut off at 
seventy pounds, and the pressure in the main 
reservoir and trainpipe would be the same, but 
if the handle is in running position the excess 
pressure valve will not open to admit air into 
the trainpipe until there is twenty pounds in the 
main reservoir, and as it requires twenty pounds 
to hold this valve open, the trainpipe will get a 
pressure of seventy pounds before the pump 
will shut off, thus leaving an excess pressure of 
twenty pounds in the main reservoir. 

If the handle is placed on lap while the train- 
pipe pressure is below seventy pounds, the 
pump will run the main reservoir pressure up to 
boiler pressure, for the governor cannot shut the 
pump off unless there is seventy pounds in the 
trainpipe; on the other hand, if the handle is in 
running position no air can get into the train- 
pipe until there is twenty pounds of excess in 
the main reservoir, and as a consequence the 
many leaks that commonly occur in the main 
reservoir and trainpipe connections cause the 
brakes to creep on before the pressure can be 
restored to keep them off. It was mainly on 
this account that the F-6 brake valve was 
invented, for with this valve the pump governor 



122 MODERN AIR-BRAKE PRACTICE 




Fio.4 

PLATE NO. 18. D-8 BRAKE VALVE AND ROTARY. 



DESCRIPTION OF PLATE 1 8 — D-8 BRAKE VALVE 

Fig. 2 shows trainpipe exhaust n, n, 25. 

21. Excess pressure valve. 

Fig. 4. The rotary valve and handle. 



lis USE AND ABUSE 123 

i., controlled by the main reservoir pressure, and 
will stop the pump at ninety pounds in the main 
reservoir, no matter in what position the handle 
is, and, as the trainpipe pressure is controlled by 
the feed valve, whenever that pressure falls 
below the standard of seventy pounds, if the 
handle is in running position the feed valve will 
open and let the main reservoir pressure in, and 
thus keep the brakes from dragging. 

Another difference between the two kinds of 
brake valves is that with the D-8 valve, when 
making a service application, the air from cavity 
D over the equalizing discharge valve (17) is 
exhausted to the atmosphere through a separate 
little port in the casing, marked h in Fig. 2 of 
plate 18, whereas the preliminary exhaust h, in 
the F-6 valve, is connected with the main or 
emergency exhaust, marked k in Fig. 2 of plate 
20, thus making one port less through the casing 
of the F-6 brake valve. 

Therefore there are the following differences 
between the D-8 and the F-6 brake valves: ist, 
with the D-8 valve the excess pressure is gotten 
before the trainpipe begins to charge, if the 
handle is in running position; 2nd, with the D-8 
valve the trainpipe pressure is controlled by the 
pump governor, instead of the feed valve attach- 



124 MODERN AIR-BRAKE PRACTICE 

ment, as it is with the F-6; 3rd, with the D-8 
valve, if the handle is left in either lap, service 
or emergency position, the pump will run the 
main reservoir pressure up to boiler pressure, 
or will shut off when there is only seventy 
pounds in the main reservoir if the handle is left 
in full release from the starting of the pump, 
whereas with the F-6 valve, the pump will be 
shut off by the governor, if properly set, when 
the main reservoir reaches ninety pounds, no 
matter what position the handle of the valve is 
in; 4th, with the F-6 valve the excess pressure 
is gotten after the trainpipe pressure is pumped 
up; 5th, with the D-8 valve, if the excess pres- 
sure valve should happen to be in bad order, 
and it usually is, if the handle was left on lap for 
any considerable length of time after making a 
service application, the main reservoir pressure 
would be raised so high that, with a short train, 
when the handle was thrown to release position 
the auxiliaries would be overcharged, and the 
wheels slid on the next application, unless the 
engineer was very careful, whereas with the F-6 
valve the most that could get in the auxiliaries, 
if the governor was correct, would be ninety 
pounds; 6th, when an emergency application is 
made with the D-8 valve, the black hand on the 



ITS USE AND ABUSE 125 

gauge will rise instead of fall, because in this 
position the equalizing port to cavity D is open 
to the main reservoir pressure. The construc- 
tion of the D-8 valve, with these differences, is 
the same as the F-6 or G-6, except that the D-8 
has an excess pressure valve while the F-6 or 
G-6 has a feed valve attachment, which will be 
explained in regular order. 

PLATES IQ AND 20 — THE F-6 (i8Q2 MODEl) ENGI- 
NEER'S BRAKE VALVE 

The engineer's brake valve is the device on 
the engine by means of which the engineer is 
enabled to charge up, and keep charged, the 
trainpipe and auxiliaries; apply the brakes, and 
keep them applied, release the brakes, and keep 
them released, and to do these several things he 
has either to place the main reservoir in com- 
munication with the trainpipe, or open the train- 
pipe to the atmosphere, or shut off all communi- 
cation, as the case may be, according to whether 
he is applying or releasing the brakes, keeping 
them set, or running along. 

There are just four things that constitute the 
essential parts to a modern brake valve, and 
they are: the rotary valve, the handle that con- 
trols the rotary, the equalizing discharge valve, 



126 MODERN AIR-BRAKE PRACTICE 

and the feed valve attachment, or trainpipe gov- 
ernor. Of course there are gaskets, springs, 
packing rings, the equalizing reservoir, etc., but 
they are matters of detail. 

There are five positions in which the handle 
of the brake valve can be placed. 

The first, or extreme left position is "full 
release," and is the position the handle should 
always be in when releasing brakes, or when it 
becomes necessary to charge up quickly, for in 
this position the air from the main reservoir 
flows through the largest ports in the rotary 
direct into the trainpipe. 

The second position is called "running posi- 
tion," because the handle should be carried in 
this position while running along, for the reason 
that in this position the rotary valve is placed so 
that all the air that passes from the main reser- 
voir into the trainpipe must go through the feed 
valve attachment, and as this attachment will 
only allow seventy pounds of air to get into the 
trainpipe (if set correctly, and unless the high- 
speed apparatus is being used), it enables the 
pump to maintain an excess pressure in the 
main reservoir, for if the pump governor is set 
at ninety pounds, and the feed valve set at 
seventy, there will naturally be twenty pounds 



ITS USE AND ABUSE 127 

greater pressure In the main reservoir than in 
the trainpipe before the pump is stopped by the 
governor. 

Another reason why the handle must always 
be carried In running position while the train is 
running along, Is because whenever the pressure 
in the trainpipe leaks down below the standard 
of seventy pounds, the feed valve will open 
automatically and allow the main reservoir pres- 
sure to again flow into the trainpipe until that 
pressure is restored, when It will automatically 
close itself, and allow the pump to again create 
the "excess" in the main reservoir. 

The third position on the brake valve is "lap," 
and when the handle Is in this position all ports 
are closed, so that no air can pass either into the 
trainpipe or out of it. After applying the 
brakes, the handle should be brought to lap 
carefully, and held there until it is desired to 
further reduce the trainpipe pressure or release 
the brakes, as the case may be, and when releas- 
ing the brakes the handle must be placed on full 
release position for a few seconds, according to 
the length of train and the amount of excess 
carried, before it Is allowed to rest on running 
position. 

The fourth position is called "service applica- 



128 MODERN AIR-BRAKE PRACTICE 



C 8 '^MWIZZZZIT^] 



(So Pomp Qoveroor and Qaiue 
„ . BedHaud 
Main Beservoir 



I>lnat AppUioailoa 
and Supply Port 




uimeriean Machinitt 



Fig, 3 

PLATE NO. 19. — F-6 BRAKE VALVE AND OLD STYLE FEED VALVE 



ITS USE AND ABUSE 129 



DESCRIPTION OF PLATE 1 9 — F-6 BRAKE VALVE 

Fig. I is explained by small type. 

Fig. 3 shows the feed valve attachment. 

(See text for description.) 



T30 



MODERN AIR-BRAKE PRACTICE 



tion position," because in this position the air is 
allowed to escape gradually from the trainpipe. 
In this position the air on top of the equalizing 
discharge valve is allowed to escape through the 
small preliminary exhaust port in the seat of the 
rotary so gradually that a sudden reduction on 
the trainpipe is prevented, for as the pressure 
on top of the discharge valve is allowed to 
escape, the trainpipe pressure below gradually 
forces it from its seat and thereby opens the 
trainpipe exhaust. If the handle is left in serv- 
ice position until ten pounds is drawn from the 
top of the discharge valve and then placed on 
lap, the valve will not seat until a fraction over 
ten pounds has escaped from the trainpipe, 
when the pressure on top will then be the great- 
est and force the discharge valve back to its 
seat, and thereby close the trainpipe exhaust. 

The fifth position is called "emergency appli- 
cation position," because when the handle is in 
this position the rotary connects the main train- 
pipe supply port with the main exhaust port, 
and the air is allowed to escape from the train- 
pipe direct to the atmosphere, regardless of the 
equalizing discharge valve, and this sudden 
reduction of trainpipe pressure allows the triples 
to be forced to their full stroke, as explained 



ITS USE AND ABUSE 



131 



under plate 5, and thus causes the quick action, 
or emergency application. Emergency position 
should never be used except in case of danger. 
Owing to the rough manner in which some 
enginemen handle their brakes, this position is 
often called "criminal application position." 

The parts of the F-6 brake valve are as fol- 
lows: the handle, which controls the rotary, is 
marked 8, in Fig. i ; the lug (9) is forced out by 
a spring (10) so that the handle may be stopped 
in any desired position, and when placing the 
handle in any of the positions be sure that the 
lug in the handle is right up against the lug on 
the brake valve, for the reason that the rotary 
valve is moved in exact accord with the handle. 
If either lug is worn the movement of the rotary 
will be correspondingly changed when the lugs 
are against each other; 12 is the stem to one end 
of which the handle is fastened by nuts 6 and 7, 
and the other end is dove-tailed or keyed into 
the top of the rotary, so that whatever way the 
handle is turned the rotary has to turn with it; 
13 is a small leather gasket for the purpose of 
preventing any air from leaking out around the 
stem, as main reservoir pressure is always on top 
of the rotary and under the shoulder of stem 12, 
forcing it up against the casing. This gasket 



132 MODERN AIR-BRAKE PRACTICE 



fl 



rW 



Pump Con/mno* a CauS 

-BED MANO- 




PLATE NO. 20. — F-6 BRAKE VALVE. — ROTARY AND SEAT. 



DESCRIPTION OF PLATE 20 — F-6 BRAKE VALVE 

Fig. 2 shows rotary seat and five positions of 
the handle. 

Fig. 4 is the rotary and handle. 



ITS USE AND ABUSE 133 

sometimes gets gummed up so badly that it 
causes the handle to move very hard; 14 is the 
rotary valve, and 3 is the rotary valve seat; 18 is 
the equalizing discharge valve, which controls 
the trainpipe exhaust m and n. The action of 
the discharge valve has already been explained 
under "service application position." 

As cavity D above the discharge valve is very 
small, it is necessary to have a greater volume 
of air to control it than the cavity alone will con- 
tain, and this greater volume is supplied by a 
little drum, or equalizing reservoir, which holds 
about 500 cubic inches of air, and is located, 
usually, under the footboard of the cab. It is 
connected to the brake valve at T (Fig. i), and 
from T to cavity D there is a connecting pas- 
sage, as shown by s in Figs. 2 and 3, and as the 
little drum is always charged equally with cavity 
D, whenever the pressure in cavity D is reduced 
it is also reduced in the little drum. This greater 
volume is needed above the discharge valve to 
compensate for the volume in the trainpipe. 

When the handle of the brake valve is placed 
in service position the rotary shuts off the main 
reservoir and also cavity D from the trainpipe, 
and allows the air to escape from cavity D by 
way of port e, groove p and preliminary exhaust 



134 MODERN AIR-BRAKE PRACTICE 

port h to the atmosphere through the main 
exhaust k, and when the handle is moved to lap 
it closes the preliminary exhaust, and thus holds 
the little drum pressure at whatever it was 
reduced to, as shown by the black hand of the 
gauge, and when the trainpipe has exhausted 
until it becomes less than the pressure in cavity 
D the discharge valve is forced to its seat by the 
pressure in the little drum, and stops any further 
flow of air from the trainpipe. 

Nos. 34 to 46 in Fig. 3 of plate 19 all refer to 
the old style feed valve attachment as used on 
the F-6 brake valve. The essential parts are 
the supply valve (34), valve spring (35), diaphgram 
piston {;^"j)y regulating spring (39), regulating 
nut (41). 

When the rotary is in running position the 
operation of the feed valve is as follows: the 
regulating spring being set at seventy pounds 
tension, it forces the piston up against the stem 
of the supply valve and raises it off its seat, 
causing the main reservoir pressure to flow from 
the top of the rotary down through port / in the 
rotary (Fig. 4 plate 20), and through port /in the 
rotary seat (Fig. 3, plate 19), through a passage 
(/), and under the supply valve to the top of the 
diaphragm piston, then through a port (shown by 



ITS USE AND ABUSE 135 

dotted lines, and marked i, Fig. 2, plate 20), 
which leads off the top of the piston into the 
trainpipe by way of the main supply port, as 
shown by dotted lines in Fig. 2. As the rotary 
is now in position so that the large cavity (^), as 
shown in Fig. 4, plate 20, connects the main sup- 
ply port with the equalizing port ^ (which passes 
through the rotary seat into cavity D), the air 
that is passing from the top of the rotary 
through the feed valve into the trainpipe, is 
also filling cavity D, and the little drum, by way 
of ports £■ and s, as shown in Fig. 3, plate 19 
(while plate 19 shows full release position, still 
ports s and g are plainly shown, and if the 
handle was moved to running position the port 
through the rotary that registers with port e in 
Fig- 3> would be in register with port,/; poi:t g is 
indicated by dotted lines). 

In running position, when the trainpipe and 
little drum are charged up to seventy pounds 
there is also seventy pounds on top of the dia- 
phram piston, and as the regulating spring is set 
at a fraction less than seventy, the air pressure 
forces it down and allows the supply valve to 
seat and shut off the main reservoir from the 
trainpipe. But as soon as the pressure in the 
trainpipe falls below seventy, the piston is again 



136 MODERN AIR-BRAKE PRACTICE 

forced up by the regulating spring and keeps the 
supply valve open until the pressure is again 
restored in the trainpipe. 

The feed valve attachment is in operation only 
when the handle of the brake valve is in running 
position. 

The course of the air through the brake valve 
in full release position is as follows: the return 
pipe from the main reservoir is connected to the 
brake valve at X, and passes directly to the top 
of the rotary through passage A, then through 
port a in the rotary into cavity b in the rotary 
seat and under a bridge in the rotary (which 
now stands midway over cavity b), and on over 
the seat of the rotary, through large cavity Cy 
direct into the main supply port (i) to the train- 
pipe. In passing over the rotary seat the air 
also passes down through the equalizing port ^, 
into cavity D, and from cavity D through port s 
into the little drum; and as the feed valve is cut 
out when the handle is in full release, both the 
little drum and trainpipe pressure would charge 
up to main reservoir pressure if the rotary was 
left in full release. In full release position, port 
j in the rotary registers with port e in the seat, 
so that cavity D charges faster in full release 
than in running position. 



ITS USE AND ABUSE 



137 



Always remember that the little drum is sim- 
ply an enlargement of cavity D, and the same 
pressure is in both. 

The Warning Port, through which the air is 
heard escaping as long as the handle remains in 
full release, is a small port through the rotary 
about the size of a pin, which allows the main 
reservoir air to whistle through it to warn the 
engineer that he is liable to overcharge his train- 
pipe. It should always be kept clean. 

The black hand of the gauge is piped to the 
little drum at W (Fig. i, plate 19), as stud 17 is 
tapped into pipe 15 which connects the little 
drum with cavity D by way of port s. 

The red hand of the gauge and also the pump 
governor are piped to the main reservoir pres- 
sure at R. 

To make an emergency application the handle 
must be moved to the extreme right, when the 
large cavity (c) in the rotary will connect the 
main supply port (/) of the trainpipe with the 
main exhaust port (k)y and allow the air in the 
trainpipe to exhaust directly into the atmosphere. 

PLATES 21 AND 22 — THE G-6 BRAKE VALVE AND 
NEW SLIDE VALVE FEED VALVE 

The G-6 brake valve is identical with the F-6, 
with the exception of the feed valve. In the 



138 MODERN AIR-BRAKE PRACTICE 




PLATE NO. 21. G-6 BRAKE VALVE. 



DESCRIPTION OF PLATE 21 — G-6 BRAKE VALVE 

Fig. 3 shows how the new slide valve feed 
valve is attached. 



ITS USE AND ABUSE 139 

new slide valve feed valve the only material 
change is that a slide valve controls the flow of 
air from the main reservoir into the trainpipe, 
which allows the pressure to be raised much 
quicker than it can be with the old style feed 
valve. 

The w^orking parts of the new slide valve feed 
valve are as follows: all of the essential parts of 
the old style feed valve are retained, as shown 
by plate 22, with slight modification, for 64 Is the 
diaphragm piston, which instead of having a rub- 
ber diaphragm has two sheet-brass diaphragms 
(57) on the piston head, supported by a ring (63); 
67 is the regulating spring; 65 the regulating nut; 
59 a small valve corresponding exactly with sup- 
ply valve 34 in the old style feed valve, and 60 is 
the spring which controls valve 59. 

By plate 21, Fig. 3, you will see that there is a 
slide valve (55) attached to a piston (54), and this 
piston is forced forward by a spring (58). 

The action of the new slide valve feed valve is 
as follows: when the handle of the rotary is in 
running position, main reservoir pressure drives 
the slide valve and piston back, which uncovers 
a port in the slide valve seat that connects with 
feed port iy and as the slide valve does not move 
until the trainpipe is fully charged, it causes the 



140 MODERN AIR-BRAKE PRACTICE 




63 62 66 

PLATE NO. 22. — SLIDE VALVE FEED VALVB. 



DESCRIPTION OF 



PLATE 22- 
VALVE 



-SLIDE VALVE FEED 



57. Diaphragm piston. 

59. Cut-off valve. 

67. Regulating spring. 

65. Regulating nut. 

The slide valve is shown in plate 21. 



ITS USE AND ABUSE 141 

pressure to be restored very quickly after it has 
been reduced from any cause. 

The reason the slide valve does not move until 
the pressure is restored is because the piston has 
no packing rings, and the air is allowed to cir- 
culate by it through a small passage that leads to 
the supply valve chamber, from which it passes 
under the cut-off valve across the diaphragm into 
feed port i, and when there is a pressure of 
seventy pounds on the diaphragm it moves away 
from the supply valve and allows it to seat, when 
the circulation by the piston is stopped, causing 
the pressure to equalize on both sides of the 
slide valve piston, when spring 58 moves the 
slide valve and closes communication between 
the main reservoir and the trainpipe. When- 
ever trainpipe pressure falls below seventy the 
diaphragm forces valve 59 off its seat and the 
same action is repeated as before. 

THE HIGH-SPEED BRAKE 

Briefly stated, the high speed brake is an 
apparatus which enables the engineer to apply a 
very high pressure to the brake cylinders while 
running at a high speed, which automatically 
reduces as the train slows down. 

When a train is equipped with the high-speed 



142 MODERN AIR-BRAKE PRACTICE 




PLATE NO. 23 — HIGH-St>EED BRAKE. 



ITS USE AND ABUSE 14 



DESCRIPTION OF PLATE 23 — HIGH-SPEED BRAKE AS 
ATTACHED TO CAR 

This illustration shows how the reducing valve 
is attached to a car and piped to the pressure 
head of brake cylinder. 



144 MODERN AIR-BRAKE PRACTICE 

brake a pressure of no pounds is carried in the 
trainpipe and auxiliaries and 120 in the main 
reservoir. 

The equipment for the high-speed brake is the 
same as the ordinary quick-action brake, except 
that there is a duplex pump governor, an addi- 
tional slide valve feed valve, a quick action 
instead of a plain triple on the tender, a specially 
designed plain triple for the driver and truck 
brakes, and an automatic reducing valve attached 
to the cylinder under the tender and each car, 
as shown in plate 23. 

As the high pressures are only to be used on 
trains which run at a very high speed, there are 
cut-out cocks on the pump governor and feed 
valves so that the regular seventy and ninety 
pounds can be carried when required. 

When it is desired to change the locomotive 
equipment from the quick-action to the high- 
speed brake it is only necessary to turn two 
handles, that of the reversing cock of the feed 
valve and that of the quarter-inch cut-out cock 
on the pipe leading to the governor. These 
handles must be turned at right angles to the 
position occupied when the quick-action brake 
is being used. 

The duplex pump governor consists merely of 



ITS USE AND ABUSE 145 

two diaphragm portions of the ordinary pump 
governor (only one of which is in use at a time) 
connected with one steam valve portion. 

The principle of the high-speed brake is as 
follows: As the friction between the shoe and 
the wheel is lessened as the rapidity of rotation 
of the wheel increases, and as the adhesion 
between the wheel and rail remains practically 
the same regardless of speed, a greater cylinder 
pressure can be used while the train is moving 
at a high speed without danger of sliding wheels, 
but as the train slows down the cylinder pressure 
must be correspondingly reduced. This is done 
by what is called the automatic reducing valve. 

PLATE 24 — THE AUTOMATIC REDUCING VALVE FOR 
THE HIGH-SPEED BRAKE 

Attached to the brake cylinder on each car 
there is an automatic reducing valve. Fig. 2 
shows how the air passes in at Z, through a 
strainer (17), and, if the pressure is above sixty 
pounds, it overcomes the tension of regulating 
spring II, and piston 4 is forced down, which 
carries the slide valve (8) with it, so that port b 
in the valve registers with port a in the seat, and 
allows the surplus pressure to escape to the 
atmosphere until the cylinder pressure is down 



146 MODERN AIR-BRAKE PRACTICE 



EXHAUST 

Y 




Z'-TO BRAKE CrUNOER 



PLATE NO. 24 — THE AUTOMATIC REDUCING VALVE. 



TS USE AND ABUSE 147 



DESCRIPTION OF PLATE 24 — AUTOMATIC REDUCING 

VALVE 

10. Cap nut. 

9. U spring of slide valve. 

8. Slide valve. 

6. Slide-valve piston. 

11. Regulating spring. 

12. Regulating nut. 



148 MODERN AIR-BRAKE PRACTICE 

to sixty pounds, when the regulating spring 
forces the slide valve up and thereby closes the 
exhaust port a, and holds the sixty pounds in 
the cylinder until the engineer releases the brake 
in the usual way. 

Plates 25, 26 and 27 illustrate the positions of 
the ports in the valve seat and slide valve of the 
reducing valve when making a service stop, an 
emergency stop, or when there is sixty pounds or 
less in the cylinder. 

The opening d in the side of the slide valve 
always admits cylinder pressure to port b, and, 
as port b is triangular in form, when a service 
stop is made the largest end of port b is in register 
with port a, to allow the air to reduce as rapidly 
as possible from the cylinder, but when an 
emergency application is made the slide valve is 
forced down so that the small end of port b is in 
register with port a, and as the surplus cylinder 
pressure is gradually exhausted the regulating 
spring gradually raises the slide valve until, 
when there is a fraction less than sixty pounds 
left in the cylinder, port b is beyond port a, and 
the exhaust is closed. 

The air remaining in the cylinder is released 
in the usual manner, by way of the triple exhaust. 

The reducing valve should be examined occa- 



ITS USE AND ABUSE 



149 



TO BRAKE 

2 

CYUIMOER 




POSITION OF PORTS. 
SERVICE STOP. 
PRESSURE EXCEEDING 60 POUNDS 
IN BRAKE CYLINDER. 

PLATE NO. 25. — SERVICE STOP. 



DESCRIPTION OF PLATE 25— SERVICE STOP 

8. Face of slide valve, showing large end of 
port d to be in register with exhaust port a. 



I50 MODERN AIR-BRAKE PRACTICE 

sionally in order to detect and overcome any 
possible leak through the discharge port. 

Cars that are not equipped with the automatic 
reducing valve should never be attached to 
trains employing the high-speed brake, unless 
the brake cylinders are equipped with the safety 
valve provided for temporary use in such cases. 
The safety valve has been especially designed 
to prevent a higher than standard pressure in 
the brake cylinders of cars not equipped with 
the automatic reducing valve. It may be quickly 
screwed into the oiling hole of the brake-cylin- 
der head and removed when the car is again 
placed in ordinary service. 

HIGH-PRESSURE CONTROL OR SCHEDULE U 

The purpose of the high-pressure control 
equipment is to enable enginemen to safely 
handle freight trains which are hauled out 
empty and brought back loaded. 

For example, all freight-brake rigging is sup- 
posed to be adjusted so that the brake power 
exerted will be equal to only seventy per cent 
of the light weight of the car with a seventy- 
pound auxiliary pressure, and when you load a 
car, you of course change its weight; conse- 
quently if the brake power on an empty car 



ITS USE AND ABUSE 



151 




POSITION OP PORTS. 
EMERGENCY STOP. 

PLATE NO 26. — EMERGENCY STOP. 



DESCRIPTION OF PLATE 26 — EMERGENCY STOP 

8. Face of slide valve, showing small end of 
port b to be in register with exhaust 
port a. 



IC2 MODERN AIR-BRAKE PRACTICE 



should be only seventy per cent, that percentage 
would be very materially lowered when you 
increase the weight by loading the car. Even 
a very light load will materially change the per- 
centage of brake power. As it would be very 
difficult to change the percentage of brake 
power by altering the brake rigging every time 
the weight of a train was changed (although 
this has been tried by using a lever shifting 
attachment) it is at once seen that the easiest 
and most practical way out of the difficulty is to 
change the standard of pressure carried in the 
auxiliary reservoir, and it is with this object in 
view that freight locomotives are equipped with 
the high-pressure control, for with this equip- 
ment an engineer can change his air pressure 
from 70 and 90 pounds to 90 and 110 pounds by 
simply turning a cut-out cock, and thereby 
increasing the percentage of brake power on his 
train. 

To make this plain to you I will explain by 
saying that if the brake-piston travel on a car is 
eight inches, and you make a service application 
of thirty pounds from a seventy-pound auxiliary 
and trainpipe pressure you would simply get 
fifty pounds in your brake cylinder, and would 
be wasting ten pounds of your trainpipe pres- 



ITS USE AND ABUSE 



153 




POSITION OF PORTS. 

REUCASC. N^ 



PLATE NO. 27. — RELEASE POSITION. 



DESCRIPTION OF PLATE 27 — RELEASE POSITION 

8. Face of slide valve, showing port b closed 
to exhaust port a. 



154 



MODERN AIR-BRAKE PRACTICE 



sure, because the auxiliary and brake cylinder 
would have equalized at fifty pounds with a 
twenty pound trainpipe reduction. Now, if you 
should have ninety pounds in the auxiliary you 
would have to draw off about twenty-six pounds 
in order to equalize the auxiliary and brake cyl- 
inder pressures, but they would equalize at about 
sixty-seven pounds, thereby giving you much 
more brake power with a full service application 
than you would ordinarily get from a seventy- 
pound trainpipe pressure with an emergency 
application. The reason for this is because the 
auxiliary and brake cylinder will equalize at a 
point (f) two-sevenths below the original auxil- 
iary pressure. For example, a 20-pound reduc- 
tion from a 70-pound auxiliary pressure will 
equalize at 50, and 20 is two-sevenths of 70. 

By this arrangement an engineer can greatly 
increase the brake power on his train so that he 
has it under better control in descending grades, 
and with little or no chance of sliding wheels, 
for the reason that the increased load not only 
makes the increased cylinder pressure safe, but 
absolutely essential. 

As a precaution against sliding wheels on the 
engine and tender, there is attached to them 
safety valves which automatically let out all 



ITS USE AND ABUSE 155 

but fifty pounds of the brake cylinder pressure 
when an application is made. 

The difference between the high-pressure con- 
trol and the high-speed brake equipments are as 
follows: the cars require no additional parts 
when using the high-pressure control; safety 
valves are used on the engine and tender instead 
of automatic reducing valves, and plain triple 
valves are used on both the locomotive and ten- 
der brakes, whereas a quick-action triple is used 
on the tender with the high-speed brake. The 
duplex pump governor is piped to both the main 
reservoir and slide valve feed valve with the 
high pressure control, whereas with the high- 
speed brake equipment the governor is piped 
direct to the main reservoir. 

Owing to the fact that the ninety-pound pump 
governor is piped to the feed valve and because 
the feed valve is automatically cut out by the 
action of the rotary whenever the handle of the 
brake valve is in any other position but running 
position, it will be seen that when the handle of 
the brake valve is in either full release, lap, 
service or emergency position the iio-pound 
governor controls the pump, thereby causing it to 
quickly pump up the excess pressure necessary 
for a sure and prompt release of the brakes, 



156 MODERN AIR-BRAKE PRACTICE 

after either a service or emergency application. 
With the high-speed brake the governor is 
piped direct to the main reservoir, the same as 
with the quick-action equipment, consequently 
the cutting in or out of the ninety-pound gov- 
ernor by the quarter-inch cut-out cock on the 
governor pipe will give you the low or high 
pressure as desired. The reason for having but 
one cut-out cock for the two governors with the 
high-speed brake is because if you cut in the 
ninety-pound governor the steam valve will be 
closed at ninety pounds, and if you cut out the 
ninety-pound governor it will require 120 pounds 
to unseat the diaphragm valve in order to let 
the air shut off the steam valve. The tension 
of the steam valve spring is, of course, always 
the same no matter which governor is in use, 
but the tension of the diaphragm spring (41) is 
regulated by nut 40, so that one diaphragm valve 
will be lifted by ninety and the other by 120 
pounds, or, if you are using the high pressure 
control, at ninety and no pounds. 

COMBINED STRAIGHT AIR AND AUTOMATIC ENGINE 

BRAKE 

A very good addition, indeed, to the air-brake 
system has recently been made by what is known 



ITS USE AND ABUSE 157 

as the Combined Straight Air and Automatic 
Engine Brake. Beside the regular apparatus 
used with the automatic brake, the equipment 
consists of the following parts: a double check 
valve for the purpose of automatically shifting 
the connection from the cylinder to either the 
triple valve or the straight air-brake valve, as 
the case may require; a straight air-brake valve, 
having three positions, release, lap and applica- 
tion; a slide valve feed valve, set at forty-five 
pounds, and attached to the straight air-brake 
valve, to reduce the main reservoir pressure 
when using straight air. The double check 
valve is used on both the engine and tender 
brakes. 

PLATE 28 — THE DOUBLE CHECK VALVE 

The double check valve consists of a casing 
(2-3) with two end and two side openings, and 
has inside a loose, spool-shaped piece w^ith a 
leather seat on each end (7) for the purpose of 
making a joint with the valve seat (a-b) at either 
of the end openings, against which it is driven 
by the air pressure entering at the other. The 
pipe leading from the straight air-brake valve is 
connected to one end opening of the double 
check valve, and the pipe from the triple is con- 



158 MODERN AIR-BRAKE PRACTICE 



BRAKE CYLINDER., 




TO BRAKE CYUN-DER, 



OR FOFi\SAFErY VALVE. 

PLATE NO. 28. — DOUBLE CHECK VALVE. 



DESCRIPTION OF PLATE 28 — DOUBLE CHECK VALVE 

4. Bushing. 

5. Check valve. 

a and d. Valve seat. 
Cy c. Ports for "straight air." 
c\, ci. Ports for "automatic." 
7. Leather gasket. 



ITS USE AND ABUSE 159 

nected to the other end opening, and the con- 
nection with the brake cyHnder is made by a 
pipe leading from either of the side openings, 
and to the other side opening is attached a 
safety valve set at about fifty pounds. 

Plate 28 shows the double check valve when 
straight air is being used, for as the air from the 
brake valve strikes the check valve it is forced 
against seat b, which shuts off the triple and 
opens port Cy which allows the air to rush into 
the cylinder. 

To release the brake the engineer simply 
places the handle of the brake valve on release 
position and the air in the cylinder returns 
through the same ports in the check valve and 
escapes to the atmosphere by way of the release 
port in the brake valve. 

To apply the brakes with the automatic brake 
valve, the straight air-brake valve must be in 
release position, and when using the straight air 
the automatic brake valve must be left in run- 
ning position. 

When a reduction is made on the trainpipc 
pressure in the usual way, with the automatic 
brake valve, the air from the auxiliary forces 
the check valve against seat a, and thereby 
opens ports c\, which allows the auxiliary air to 



l6o MODERN AIR-BRAKE PRACTICE 




PLATE NO. 29a. BRAKE VALVE AND COMBINED STRAIGHT AIR 

AND AUTOMATIC ENGINE BRAKE. 

{For description see following page.) 



r\ 




PLATE NO. 29b. — BRAKE VALVE AND COMBINED STRAIGHT AIR 
AND AUTOMATIC ENGINE BRAKE. 



Description of Plates 29a and 29b. — 2. Shaft attached to handle 
(4) for operating valve 8 and release valve 9. The handle is on 
lap position. 

161 



i62 MODERN AIR-BRAKE PRACTICE 

rush into the cylinder. The brake is released 
in the usual way, for when the automatic brake 
valve is placed in full release position the triple 
piston reverses the slide valve, and the exhaust 
being thus opened the air in the cylinder flows 
back through ports ci in the check valve and 
out through the triple exhaust. 

When an engineer wishes to do so he can 
keep his train brakes released and still have his 
engine and tender brakes set, when his engine 
is equipped with this special apparatus. 

PLATES 29 AND 30 — THE STRAIGHT AIR-BRAKE 
VALVE 

The straight air-brake valve has three posi- 
tions: release, lap and application. Plates 29 
and 30 show it on lap. It is very simple, as the 
essential parts are the handle (4); the shaft (2), 
to which the handle is fastened, which operates 
two check valves (8 and 9). Check valve 8 con- 
trols the supply of air from the main reservoir 
to the brake cylinder, and valve 9 controls the 
exhaust from the cylinder. 

Look at plate 29A and imagine that you have 
moved the handle to the right, which would 
cause the shaft to force valve 8 down and allow 
main reservoir pressure, which is always in 



ITS USE AND ABUSE 163 

chamber a, to flow under the valve into passage 
b and through b\ (plate 30), b2 and X (plate 29B) 
to the double check valve and on into the 
cylinder, as explained under plate 28. 

To release the brake, the handle is moved 
back to the extreme left, which causes the shaft 
to allow valve 8 to reseat, and forces valve 9 
down, when the air from the cylinder passes 
back through X, <^2, under valve 9, through pas- 
sage c to the exhaust. 

The slide valve feed valve is attached to the 
pipe leading to the double check valve, and 
when the handle is thrown to application posi- 
tion the flow of air from the main reservoir to 
the cylinder is shut off automatically at forty- 
five pounds. Should the feed valve leak, or be 
set too high, the safety valve will allow the sur- 
plus pressure to escape, and should the safety 
valve not seat properly it would allow the cylin- 
der pressure to leak off when either a straight 
air or automatic application was made. 

PLATE 31 — THE WHISTLE SIGNAL SYSTEM 

There are four essential things that go to 
make up the air-signal system, aside from the 
pipes, cut-out cocks, cords, etc. 

Fig. I is the signal valve, and stands in the 



i64 MODERN AIR-BRAKE PRACTICE 




€rCH/IU€T^ 



TODOOBLe 
CtieCtt V4LV£ 



PLATE NO. 30. BRAKE VALVE FOR COMBINED STRAIGHT AIR 

AND AUTOMATIC ENGINE BRAKE. 

{^For description see following page.) 



ITS USE AND ABUSE 



165 



/^-N 



DESCRIPTION OF PLATE 30 

Section F.F. shows how 
the air passes from the 
main reservoir by way of 
valve 8 to the double 
check valve, and how in 
returning from the double 
check valve it passes un- 
der valve 9 to the ex- 
haust. 




PLATE NO. 30. — BRAKE VALVE FOR COMBINED STRAIGHT AIR 
AND AUTOMATIC ENGINE BRAKE. 



i66 MODERN AIR-BRAKE PRACTICE 

same relation to the whistle as the auxiliary does 
to the brake cylinder, for it is in the signal valve 
that the air is stored for use in blowing the 
whistle. 

Fig. 2 is the car discharge valve, and stands in 
the same relation to the air signal as the con- 
ductor's valve does to the air brake, for when the 
car discharge valve is opened the air escapes 
from the signal pipe and causes the whistle to 
blow. 

Fig. 3 is the whistle. 

Fig. 4 is the improved reducing valve, which is 
to the air signal what the feed-valve attachment 
is to the air brake, as it controls the pressure in 
the signal pipe and signal valve. 

The reducing valve is identical in its operation 
with the old style feed-valve attachment, and 
when you understand one you know the other, 
for as the regulating spring 13 is set at forty 
pounds, the diaphragm piston (10) will keep the 
supply valve (4) off its seat until the main reser- 
voir pressure (which flows in at A) has filled the 
signal pipe (B) to a fraction over forty pounds, 
when the piston is forced down and allows the 
supply valve to shut off the main reservoir pres- 
sure until the signal-pipe pressure is again 
reduced, when the piston will again raise and 



ITS USE AND ABUSE 167 

unseat the supply valve to allow the main reser- 
voir to quickly restore the pressure in the signal 
pipe, when the valve will again seat by the pis- 
ton being forced away from it. 

The signal valve is attached to the main sig- 
nal pipe by a short branch pipe at Y, and what- 
ever pressure is in the pipe the same is in 
chambers A and B, for as air passes through 
port d into chamber A, it also passes down pas- 
sage C and raises the diaphragm stem (10) so 
that the small groove cut around the stem at/ 
is above bushing 9, and as the side of the stem 
is flat as far up as the groove, when the stem is 
raised the air is free to enter chamber B, and 
when it equalizes with A the stem drops to its 
seat (7) by its own weight and closes port e. 
The stem is attached to a rubber diaphragm 
(12), and as the whistle is piped to the signal 
valve at X, whenever the lever (5, Fig. 2) of the 
car discharge valve is moved either to the right 
or left the small valve (3) is forced off its seat to 
allow the air to escape from the signal pipe, and 
when the pressure is thus reduced the air in 
chamber A is also reduced, and as the volume 
of B is so much greater than A the rubber dia- 
phragm is forced up, which unseats the stem 
and allows the air in B and some of the signal- 



i68 MODERN AIR-BRAKE PRACTICE 




PLATE NO. 31. — WHISTLE SIGNAL SYSTEM. 



ITS USE AND ABUSE 169 



DESCRIPTION OF PLATE 3 1 — WHISTLE SIGNAL 
SYSTEM 



Fig. I. Whistle signal valve. 
Fig. 2. Car discharge valve. 
Fig. 3. The whistle. 
Fig. 4. Reducing valve. 



lyo MODERN AIR-BRAKE PRACTICE 

pipe air to rush out through the bell-shaped 
whistle and cause it to blow. 

In order to insure the whistle giving the 
proper blast it is necessary to make a sudden 
reduction, and as it is the air in the signal valve 
that blows the whistle, at least two seconds must 
be allowed between each pull of the cord to let 
chamber B fully recharge, and on a long train 
four seconds is better. 

Plates 32 and 33 are diagrammatic illustrations 
showing (32) the Quick-Action Automatic Brake, 
and (33) the High-Speed Brake Equipment. 
These plates are remarkably complete in detail, 
and the reader will at once see the exact rela- 
tion each part is to the other. 



? 



a 






J c=!i- 



r 



.^^03 TN>0 x\jO 



rfp 



ff 



^ 



QIP^AOB OVS\V\VN.\i^ CfT VSi 







~M 



"^Hl 



u 



fn>'V 




^^^T3A-^0^ 



.riA" 



CT3z 







ONE INCH MINE 



AND ONE HALF fNCH 




QUESTIONS AND ANSWERS TO 
SECTION I 

THE PARTS OF THE AUTOMATIC AND HIGH SPEED 
AIR-BRAKE EQUIPMENT AND THEIR DUTIES 

1. What is meant by an automatic brake? 
Ans. — A brake that is self-acting. 

2. When an engine is equipped with the Wes- 
tinghouse automatic quick-action air brake, what 
are the essential parts, and what are their duties? 

Ans. — A steam-driven pump to compress the 
air; a main reservoir in which the air is stored 
ready for use; an automatic air-controlled gov- 
ernor for stopping and starting the pump accord- 
ing to the amount of compressed air required in 
the brake apparatus; a duplex gauge for regis- 
tering the pressure in the main reservoir and 
trainpipe; an engineer's brake valve for control- 
ling the flow of air from the main reservoir into 
the trainpipe and from the trainpipe to the 
atmosphere; an equalizing reservoir attached to 
the brake valve for controlling the equalizing 
discharge valve within the brake valve; pipe 

connections between the pump and the main 

173 



174 MODERN AIR-BRAKE PRACTICE 

reservoir, between the main reservoir and the 
brake valve, between the main reservoir and the 
governor, between the main reservoir and the 
red hand of the gauge, between the equalizing 
reservoir and the black hand of the gauge, rep- 
resenting trainpipe pressure; and to the brake 
valve is attached the trainpipe, in which is 
located a cut-out cock just below the brake 
valve for the purpose of closing communications 
between the brake valve and trainpipe as occa- 
sion demands, as in double heading; branch 
pipes leading from the trainpipe to the triple 
valve, from the triple valve to the auxiliary 
reservoir, from the triple to the brake cylinders, 
as there are two brake cylinders on the engine 
the pipe leading from the triple to the cylinders 
is teed so that one branch leads to the right and 
the other to the left-hand cylinder; there are 
cut-out cocks on the branch pipe leading from 
the trainpipe to the triple and from the triple to 
the brake cylinder, and from the triple to the 
auxiliary; there is an auxiliary reservoir for sup- 
flying air to the brake cylinder and a plain 
triple valve for charging, setting, and releasing 
the brake. When an engine is said to be fully 
equipped there is also a truck brake equipment 
consisting of an additional auxiliary reservoir of 



ITS USE AND ABUSE 175 

smaller capacity, a truck brake cylinder and an 
automatic slack adjuster. 

3. What additional apparatus is required on a 
passenger engine from that of a freight engine? 

Ans. — The whistle signal equipment, consist- 
ing of a reducing valve set at forty pounds, a 
whistle signal valve, and an air whistle, together 
with a signal pipe and suitable connections 
between the main reservoir and reducing valve, 
and from the reducing valve and signal valve, 
and from the signal valve to the air whistle. 

4. What additional apparatus is needed to 
change the quick-action equipment into a high- 
speed equipment? 

Ans. — A duplex pump governor, an extra slide 
valve feed valve and bracket, and an automatic 
reducing valve. 

5. What are the parts required on a tender in 
ordinary freight or passenger service? 

Ans. — A trainpipe, brake cylinder, auxiliary 
reservoir and a plain triple valve with branch 
pipes, cut-out cocks, an angle-cock and hose. 
In passenger service there is, in addition, the 
signal pipe with its angle-cock and hose. 

6. W^hen equipped for high-speed brake, what 
additions are needed on a tender? 

Ans. — An automatic reducing valve set at 



176 MODERN AIR-BRAKE PRACTICE 

sixty pounds, and the quick-action triple is sub- 
stituted for the plain triple. To be fully equipped 
the tender in any kind of service should also 
have an automatic slack adjuster and a release 
signal. 

7. What apparatus is required on a freight car? 

Ans. — A trainpipe with angle-cocks and hose 
at both ends; a quick-action triple valve; a 
brake cylinder; a branch pipe leading from the 
trainpipe to the triple in which is a cut-out cock; 
a release rod leading from the release valve on 
the auxiliary to either side of the car; a pres- 
sure-retaining valve clamped to the end of the 
car near the top along side the staff of the hand 
brake; a pipe connecting the retaining valve 
with the triple exhaust so that when it is desired 
to allow the engineer to recharge the auxiliary 
reservoir on descending grades the handle of 
the retainer can be turned up and thereby retain 
a pressure of fifteen pounds in the brake cylin- 
der at the same time (at the foot of the grade, 
or sooner if desired, the handle must be turned 
down again in order to permit the engineer to 
release the brakes); on the other end of the car 
from the retaining valve there should be a 
release signal, which is clamped to the end of 
the car just below the top and piped direct to 



ITS USE AND ABUSE 177 

the brake cylinder, the purpose of which is to 
signal the train crew every time the brake sets, 
releases, leaks off, has too much piston-travel or 
sticks. It also enables the trainmen to detect a 
"kicker," or brake that flies into emergency with 
a service application. When a brake sticks so 
that it cannot be released from the engine the 
brakeman can release it from the top of the car 
by simply holding down the valve which is on 
the end of the signal staff until the signal drops 
into its pocket. On a dark night when the 
brakes are felt to be dragging, the brakeman 
will not have to drop off and watch the brakes 
as the train passes in order to find the defective 
brake, but can, when the release-signal is used, 
run back over the top of the train, and by the 
light of his lantern, see the release-signal as it 
appears above the top of the car, as it is a foot 
square, and having thus quickly and surely found 
it, has only to push the valve down and let the 
brake off without having to take any personal 
risk, as he does when dropping off the train, and 
without causing a dangerous delay to the train, 
as is frequently the case when brakes get to 
dragging and have to be bled off by the auxiliary 
release valve. Whenever the air is out of the 
brake cylinder the release-signal will automati- 



178 MODERN AIR-BRAKE PRACTICE 

cally drop into its pocket below the top of the 
car. To find a "kicker" in a train, have the 
engineer make a five-pound reduction, and on 
all cars on which the triple valves are properly 
working the signal will show itself just a little 
way above the top of the car. In case the 
"kicker" should be caused by a weak graduating 
spring in one of the first seven cars, it would 
throw the whole train in emergency on the first 
light reduction, but on the car w^hich has the 
"kicker," if it is not caused by a weak graduating 
spring in the first seven cars, the signal will not 
move with the first five-pound reduction, so that 
when the next five-pound reduction is made, the 
signal which did not move at all on the first 
reduction will jump up, showing that the defect- 
ive triple is on that particular car. Having 
thus found the "kicker," cut that brake out, card 
the car and report as usual. As uneven piston- 
travel is one of the worst evils railroads have to 
contend with, all air brake cars should also be 
equipped with the automatic slack-adjuster. 

8. On a passenger coach, in ordinary service, 
what additional apparatus is required from that 
of a freight car? 

Ans. — A conductor's valve on the end of a 
pipe which leads from the trainpipe to within 



ITS USE AND ABUSE 179 

the body of the coach, (usually in the toilet 
room), by means of which the conductor can 
stop the train, if desired, by letting the air out 
of the trainpipe either gradually or suddenly, 
according to circumstances. For an ordinary 
stop it should be opened gradually, but for 
an emergency it should be pulled wide open 
quick and held open until the train comes to a 
full stop, when it should be again closed. On 
a passenger car there is a whistle pipe from 
which there is a branch pipe leading to the car 
discharge valve, and as there is a cord attached 
to the discharge valve, a sudden jerk of the cord 
will open the valve and let out signal-pipe pres- 
sure, thereby causing the whistle to blow on the 
engine; a lapse of at least two seconds should 
Le allowed between pulls in order to insure the 
correct signal, and on long trains four seconds is 
better. All passenger coaches should have the 
automatic slack-adjuster and the release-signal. 

9. To equip a passenger car for the high-speed 
brake, what extra apparatus is needed ? 

Ans. — Simply the automatic reducing valve. 
Where a car is temporarily used in a train 
equipped with the high-speed brake, a safety 
valve must be screwed into the oil hole of the 
brake cylinder, and when it is returned to ordi- 



i8o MODERN AIR-BRAKE PRACTICE 

nary service the safety valve should be removed 
and the plug replaced in the oil hole of the 
cylinder. Ordinary passenger coaches do not 
usually have retaining valves on them, but all 
Pullman and most private cars do, and are 
placed on the end of the car in the vestibule. 

10. Now, to return to the engine equipment. 
How many main pistons are there in the pump? 

Ans. — Two; the main steam piston and the 
main air piston, the former in the top and the 
latter in the bottom section of the pump. 

11. Are these pistons connected together? 
Ans. — Yes. One piston rod operates both. 

12. What is the principal difference in the 
construction of the eight-inch pump from that of 
the 9>^-inch pump? 

Ans. — The eight-inch pump has its steam 
valves on the side and top, while the 95^-inch 
pump has its steam valves all at the top, and 
where in the eight-inch pump the flow of steam 
is controlled by pistons with packing rings, in 
the 9>^-inch pump the flow of steam is con- 
trolled by a common D slide valve actuated by 
two pistons of unequal diameter. Both pumps 
contain a reversing valve with reversing valve 
rod which operates within the hollowed-out 
main piston rod. 



ITS USE AND ABUSE i8i 

13. What difference is there in the two pumps 
in regard to the air valves? 

Ans. — The eight-inch pump has its discharge 
and receiving valves all on one side, whereas in 
the 9>^-inch pump there is a receiving and dis- 
charge valve on either side of the pump. The 
eight-inch pump has two air inlets; the 9 J^ -inch 
pump has only one. 

14. Is there any difference in the lift of the air 
valves in the two pumps? 

Ans. — Yes; in the eight-inch pump the receiv- 
ing valves have a lift of }i of an inch, and the 
discharge valves have A, whereas in the 9>^-inch 
pump all air valves have a lift of ^\. 

15. Can you explain the operation of the 
steam end of the eight-inch pump? 

Ans. — When the steam enters at the side of 
the pump it flows into a chamber in which is 
contained two pistons of unequal diameter, 
which, in combination, is known as the main 
steam valve of the pump; leading from near the 
top of this chamber there is a steam passage 
which conducts the steam to the top of the 
reversing valve and from thence through a 
small passage into another chamber in which is 
contained the reversing piston (see plate 14), the 
steam having thus passed from the main valve 



i82 MODERN AIR-BRAKE PRACTICE 

chamber to the reversing valve chamber and 
into the chamber of the reversing piston, and as 
the reversing piston and the bottom piston of 
the main valve combine to make a much larger 
area than the top piston of the main valve, it 
naturally forces the main valve down so that the 
steam from the main valve chamber can pass 
through the bottom ports in the main valve 
chamber to the steam cylinder of the pump, and 
thereby force the main steam piston up; as the 
main steam piston rises, the reversing plate 
strikes the shoulder of the reversing valve rod 
and thereby changes the position of the revers- 
ing valve, so that the steam in the chamber over 
the reversing piston can pass through the second 
passage in the head through the cavity in the 
reversing valve, through the lower passage in 
the head, to the exhaust passage, which begins 
at the bottom of the reversing piston chamber 
and ends at the main exhaust. The pressure 
having now been removed from the top of the 
reversing piston, the large piston in the main 
valve chamber Is forced up, causing the small 
bottom valve to close the bottom supply ports to 
the steam cylinder and at the same time open 
the bottom exhaust ports of the steam cylinder, 
thereby allowing the steam to exhaust from the 



ITS USE AND ABUSE 183 

under side of the main piston. While the main 
valve is in this position, the exhaust port, from 
the top side of the piston, is closed, and the sup- 
ply port from the main valve chamber to the top 
of the steam piston is open, so that the steam 
can pass from the main valve chamber to the 
top of the main steam piston and thereby force 
it down; in doing so the reversing plate engages 
the button on the end of the reversing valve rod, 
which again changes the position of the revers- 
ing valve, thereby allowing the same action to 
take place as in the beginning. 

16 How do the air valves in the eight-inch 
pump operate? 

Ans. — On the up-stroke of the main air piston 
a partial vacuum is formed in the air cylinder, 
and as the atmospheric pressure is then greater 
on the outside of the ^amp, it enters the air inlet 
and forces the receiving valve off its seat until 
the air cylinder is filled with atmospheric pres- 
sure. As the reversing valve causes the main, 
pistons to reverse just before reaching the top 
of the cylinders, the compression of the air, 
which begins immediately that the piston starts 
down, causes the receiving valve to be firmly 
closed, and as the compression in the air cylin- 
der is increased over the pressure in the main 



i84 MODERN . AIR-BRAKE PRACTICE 

reservoir, it causes the discharge valve to be 
lifted and allow the air from the pump to be 
forced into the main reservoir. As the piston 
starts up again the main reservoir air holds the 
discharge valve to its seat in the same manner 
that the air cylinder pressure held the receiving 
valve to its seat on the down-stroke. In making 
the up-stroke, the upper receiving and discharge 
valves operate in the same manner as did the 
lower valves. 

17. Can you explain the operation of the steam 
end of the Q>^-inch pump? 

Ans. — The steam entering the pump at the 
main steam connection is conveyed to a cham- 
ber in the top head of the pump in which is con- 
tained two pistons of unequal diameter, on the 
piston rod of which is a common D slide valve 
moving over a seat having three ports. One of 
these ports leads to the under side of the main 
steam piston, one leads to the top of the main 
steam piston, and one to the main exhaust, and 
as the cavity in the slide valve can only connect 
two of these ports at anyone time, it naturally 
follows that when the steam enters between the 
two pistons of unequal diameter that the slide 
valve is moved towards the end of the chamber 
containing the large piston. In doing so it 



ITS USE AND ABUSE 185 

uncovers the port leading to the under side of 
the main steam piston, which causes the piston 
to move up, which in doing so operates the 
reversing valve in the same manner as previ- 
ously explained in the eight-inch pump. As the 
piston nears the top it changes the position of 
the reversing valve in order to allow steam to 
pass from between the two unequal pistons, 
through a port in the bushing, to the outer side 
of the large piston. By this action the pressure 
on both sides of the large piston is equalized, 
and as there is no pressure on the outer side of 
the small piston, the expansion of the steam 
forces the slide valve to the end of the chamber 
in which is contained the smaller piston. This 
action causes the slide valve to connect the port 
leading from the bottom side of the main steam 
piston with the port leading to the main exhaust, 
and while the steam is exhausting from the 
under side of the piston, live steam is being 
admitted to the top of the main steam piston 
through the port in the slide valve seat which is 
now uncovered, thereby forcing the main steam 
piston down, which in doing so causes the revers- 
ing valve to be reversed the same as in the 
eight-inch pump, which action exhausts the 
steam from the outer side of the large piston so 



i86 MODERN AIR-BRAKE PRACTICE 

t?iat it is again forced in the same direction as 
described in the beginning of the stroke. The 
action of the air valves is the same as in the 
eight-inch pump except that the lift of the 
valves in the 9 >^ -inch pump is A of an inch all 
around, whereas in the eight-inch pump the 
receiving valves have ^V of an inch greater lift 
than the discharge valves. 

18. What is the name of the pipe leading from 
the pump to the main reservoir? 

Ans. — The main reservoir discharge pipe. 

19. What is the name of the pipe leading 
from the main reservoir to the engineer's brake 
valve? 

Ans. — Main reservoir return pipe. 

20. What prevents the main reservoir pres- 
sure from flowing back into the pump? 

Ans. — There are two valves, known as the dis- 
charge valves, which are held to their seat by 
the main reservoir pressure, but when the pump 
compresses air to a higher pressure than that 
contained in the main reservoir, the discharge 
valves are lifted from their seat until the pres- 
sures equalize, when the valves drop to their 
seat by their own weight. 

21. If the main reservoir pressure begins at 
the pump, where does it end? 



ITS USE AND ABUSE 187 

Ans. — If the engineer's brake valve is on lap, 
it ends on top of the rotary valve and at the 
pump governor and at the red hand of the 
gauge. 

22. If the brake valve is on lap, why does not 
the main reservoir pressure end on top of the 
brake valve? 

Ans. — Because there is a branch pipe leading 
from the main reservoir pipe just before it 
reaches the brake valve, which carries the air to 
the red hand of the gauge and to the pump 
governor. 

23. Are there any other attachments which 
might consume main reservoir pressure? 

Ans. — Yes; the bell ringer and air sander, and 
if it is a passenger engine, the whistle signal 
pipe. Should a leak occur in any of these con- 
nections, It would be a main reservoir leak. 

24. Where should the main reservoir on the 
engine be located? 

Ans. — While circumstances regulate the loca- 
tion of the main reservoir, it should, however, be 
always placed in such a position that it will be 
lower than the pump, so that all oils and conden- 
sations may settle in it, and should be piped so 
that the discharge pipe, or the one which con- 
nects with the pnmp, is separated as far as pos- 



i88 MODERN AIR-BRAKE PRACTICE 

sible from the return pipe leading to the engi- 
neer's brake valve. 

25. What is the engineer's brake valve for? 

Ans. — For the purpose of enabling the engi- 
neer to properly charge, set and release brakes 
and control the flow of main reservoir and train- 
pipe pressure. 

26. What are the essential parts of the engi- 
neer's brake valve? 

Ans. — ^The rotary valve and the handle which 
controls it, the equalizing discharge valve, the 
feed valve attachment, or trainpipe governor, 
and the equalizing reservoir. 

27. What is the purpose of the rotary valve? 
Ans. — To open and close the ports in the 

brake valve. 

28. What is the handle of the brake valve for? 
Ans. — To control the movement of the rotary 

valve. 

29. What is the equalizing discharge valve for? 
Ans. — To open and close the trainpipe exhaust 

port according to the pressure above or below it. 

30. What is the equalizing reservoir intended 
for? 

Ans. — To maintain a large volume of air on 
the upper side of the equalizing discharge valve, 
in order to compensate for the volume of air in 



ITS USE AND ABUSE 189 

the tralnpipe, which is on the under side of the 
equalizing discharge valve. 

31. What is the feed-valve attachment, or 
trainpipe governor for? 

Ans. — As its name implies, it is for the purpose 
of controlling the pressure in the trainpipe. 

32. In what way does it control the pressure 
in the trainpipe? 

Ans. — As there is a regulating spring (see 
illustration) which is set at seventy pounds, it 
requires an air pressure of a little over seventy 
pounds to compress the spring and allow the 
feed valve to close and shut off the flow of air 
from the main reservoir to the trainpipe. 

33. How many kinds of feed valves are there 
in use? 

Ans. — Two. The old style feed valve is merely 
a poppet valve, while the new slide valve feed 
valve contains, in addition to the poppet valve 
feature, a slide valve, which is actuated by both 
air and spring pressure. 

34. Which feed valve is preferable and why? 
Ans. — The new slide valve feed valve; for the 

reason that with it the trainpipe pressure can be 
quickly raised and more evenly maintained, 
whereas with the old style feed valve the flow of 
air into the trainpipe is materially retarded after 



190 MODERN AIR-BRAKE PRACTICE 

the pressure has reached fifty pounds, on account 
of the gradual closing of the poppet feed valve, 
while with the new slide valve feed valve the 
trainpipe port virtually remains wide open until 
the full seventy-pounds pressure is in the train- 
pipe. While the slide valve controls the port 
leading to the trainpipe, it in turn is controlled 
by the small poppet valve, for the reason that 
when the trainpipe pressure of seventy pounds 
forces the diaphragm of the regulating spring 
away from the poppet valve, the latter is allowed 
to seat, which prevents the circulation of the air 
through the feed-valve attachment, and the 
pressure thus becomes equalized on both sides 
of the slide-valve piston. The spring behind 
the piston forces it forward and causes the slide 
valve to close the trainpipe port. It is because 
the air is intended to circulate freely on both 
sides of the slide-valve piston that there are no 
packing rings on this piston. 

35. In what position must the brake handle of 
the brake valve be in order to have the feed- 
valve attachment in operation? 

Ans. — In running position, as that is the only 
position of the brake-valve handle in which you 
can get air fropi the main reservoir to the train- 
pipe through the feed valve. 



ITS USE AND ABUSE iqi 

36. Can you trace the course of the air from 
the pump to the brake cyHnder? 

Ans. — In order to get the air from the main 
reservoir to the brake cylinder, if the handle of 
the engineer's brake valve is on lap at the begin- 
ning, it is necessary to make at least two move- 
ments of the handle of the brake valve, which I 
will explain in a moment. The pump having 
compressed the air, it is forced through the dis- 
charge valves and through the discharge pipe 
into the main reservoir, from thence it passes 
through the return pipe to the top of the rotary 
valve in the engineer's brake valve. When the 
handle of the brake valve is thrown to the left, 
or full release position, the main reservoir pres- 
sure can then pass through the largest ports in 
the brake valve direct into the trainpipe. From 
the trainpipe it passes through the branch, or 
cross-over pipe, to the trainpipe side of the 
triple piston, and in forcing the triple piston for- 
ward there is opened a feed groove in the casing 
of the triple piston cylinder, which allows the 
trainpipe pressure to flow over the piston and 
over the top of the slide valve into the auxiliary 
reservoir. The air has now been carried from 
the pump through the main reservoir, through 
the engineer's brake valve, through the train- 



192 MODERN AIR-BRAKE PRACTICE 

pipe cross-over pipe, through the triple valve 
and into the auxiliary reservoir. When a suffi- 
cient pressure has been stored in the auxiHary 
reservoir and it is desired to set the brakes, the 
engineer must move the handle of the brake 
valve to at least service application position, 
which action causes the preliminary exhaust 
port in the brake valve to open and allow the 
pressure from the top of the equalizing dis- 
charge valve to escape to the atmosphere, which 
causes the trainpipe pressure, which is on the 
under side of the equalizing discharge valve, to 
force the valve up and open the trainpipe 
exhaust port. With the trainpipe exhaust port 
open the air rushes out from the trainpipe, and 
as the triple piston stands between the trainpipe 
and auxiliary pressure, it naturally follows that 
when the trainpipe pressure has been made 
lower than the auxiliary pressure the triple pis- 
ton is forced towards the weaker pressure by the 
auxiliary pressure, and as it carries with it the 
slide valve, the ports in the slide valve and in the 
slide-valve seat are thereby opened, which allows 
the auxiliary pressure to flow into the brake cylin- 
der against the brake piston, which is connected 
with the brake levers, which forces the shoes up 
against the wheels and the brake is then set. 



ITS USE AND ABUSE 193 

37. Can you explain how the brakes are 
released? 

Ans. — By the excess pressure in the main reser- 
voir. When it is desired to release the brakes 
the handle of the brake valve is placed in full 
release position, in order that the great volume 
of air contained in the main reservoir may pass 
quickl}^ through the trainpipe and strike the 
triple piston a hammer blow, in order to over- 
come the pressure in the auxiliary reservoir, 
thereby causing the slide valve to be moved, so 
that the exhaust port of the triple valve will be 
opened and permit the brake cylinder pressure 
to pass out into the atmosphere, and the pressure 
having thus left the brake cylinder the return 
spring in the brake cylinder forces the brake 
piston back, thereby moving the brake levers to 
their original position, which allows the brake 
shoes to drop away from the wheels. 

^S. Can the brakes be released with the han- 
dle of the brake valve in any other position than 
that of full release? 

Ans. — Yes. They can be released sometimes 
in running position, but it is a very dangerous 
practice for an engineer to do so, for the reason 
that when it is necessary to release the brakes 
in a train they should be all released at the same 



194 MODERN AIR-BRAKE PRACTICE 

moment, if possible, because if some brakes 
release and others do not, it is very liable to pull 
the train in two. 

39. How many positions are there on the 
brake valve? 

Ans. — Five. Full release, running, lap, serv- 
ice and emergency. 

40. What are these positions intended for? 

Ans. — Full release is for charging and releas- 
ing the brakes. Running position is to enable 
the engineer to maintain an even pressure in 
the trainpipe and auxiliary reservoir while run- 
ning along, and keep up the excess pressure, 
because as the air in the trainpipe escapes 

■" through leaks of any kind, the feed-valve 
attachment automatically opens to allow main 
reservoir pressure to fl6w into the trainpipe, 
but automatically closes when the pressure 
has been restored. Lap position, which is the 
third on the brake valve, is for the purpose of 
closing all ports, so that no air can flow into or 
out of the trainpipe. Service application posi- 
tion is for the purpose of making a gradual 
application of brakes, and emergency applica- 
tion position is for the purpose of allowing the 
trainpipe pressure to rush out as quickly as pos- 
sible, in order that all brakes in the train may be 



ITS USE AND ABUSE 195 

set instantly, or nearly so. Emergency position 
should never be used except in case of actual or 
probable danger, and should never be used when 
an engine is on the turntable. 

41. What main reservoir and trainpipe pres- 
sures should be carried with the quick-action 
brake equipment? 

Ans. — Ninety pounds in the main reservoir, 
which is shown by the red hand, and seventy 
pounds in the trainpipe, which is shown by the 
black hand. 

42. When the high-speed brake equipment is 
used what pressure should be carried? 

Ans. — One hundred and twenty pounds in the 
main reservoir and no pounds in the trainpipe. 

43. When the high pressure control is used, 
what pressure should be used on the engine? 

Ans. — When a light train is being hauled 
there should be ninety pounds and seventy 
pounds, the same as with the quick-action brake, 
but with a loaded train there should be no 
pounds in the main reservoir and ninety in the 
trainpipe. 

44. What is meant by excess pressure, and 
what is it used for? 

Ans. — Excess pressure is the amount of air 
carried in the main reservoir over and above 



iq6 modern air-brake PRACTICE 

what is carried in the trainpipe. If the train- 
pipe governor is set at seventy pounds and the 
main reservoir or pump governor at ninety 
pounds, there would be an excess pressure of 
twenty pounds in the main reservoir. The 
object in carrying this extra or excess pressure 
is to enable the engineer to quickly recharge the 
trainpipe after making a reduction, in order to 
strike the triple pistons a hammer blow to drive 
them to release position. 



CHAPTER III 

AIR-BRAKE DEFECTS — HOW TO TEST FOR AND 
REMEDY THEM 

While a great many defects are constantly 
found in the air-brake equipment, it must be 
borne in mind that they arise more from abuse 
and neglect than from wear and tear. 

When it is taken into account that the equip- 
ment is handled by such a great variety of men, 
and is required to perform its function under 
such varying conditions, it is really amazing that 
it will remain in service as long as it does with 
out having to be renewed. But, as good as it is, 
it can easily get out of order, and the growing 
demand for greater safety in the running and 
handling of trains requires that the equipment 
be kept in as nearly perfect condition as pos- 
sible, to reduce to a minimum the recurrence of 
the terrible wrecks and accidents that will con- 
tinue to happen as long as railroads exist. 

There are many once happy homes now 
shrouded in black despair as the result of some 
air brake defect that was either neglected or 

overlooked until it was too late. For instance, 

197 



198 MODERN AIR-BRAKE PRACTICE 

an engineer on a certain road in Pennsylvania 
was pulling a heavy freight train over a moun- 
tain division, and having neglected to keep his 
air pump in proper condition, could not pump 
sufficient air to overcome the trainpipe leaks 
and still maintain the proper pressure in the 
auxiliaries, and as a consequence the braking 
power of the train gradually fell down and down 
until, upon reaching a very heavy grade, the 
train got the start of the brakes, when, like a 
crazed monster it rushed down the mountainside 
until, like a flash, it left the rails and piled up a 
mass of wreckage beneath which lay the crushed 
remains of the engineer and fireman — and as a 
result two once happy wives were thus made 
widows, not because ''the brakes failed to work," 
but because the engineer failed to maintain his 
brake equipment in the condition it should have 
been. 

I shall take up the various defects in the same 
order in which the several parts of the equip- 
ment have been described. 

The Triple Valve. The duties of the triple 
valve being to charge, set and release the brake, 
if it fails to do any one of these things it is 
because there is a defect somewhere, and if the 
trainmen expect the equipment to be kept in 



ITS USE AND ABUSE 199 

working order, they must be able to make an 
intelligent report to the car repairers. 

Failure to charge the auxiliary may be on 
account of any of the following reasons: The 
strainer being clogged, feed groove clogged, bad 
leak under the slide valve, bolts loose on triple, 
bad gaskets, or if the release valve on the aux- 
iliary does not seat properly. A very bad leak 
by the emergency valve will cause the brake to 
set while the auxiliary is being charged, and the 
air will be heard blowing out of the retainer. 

Failure to set the brake may result from not 
having sufficient pressure in the auxiliary; triple 
piston packing ring worn so that auxiliary pres- 
sure reduces as fast as trainpipe pressure is 
reduced; very dirty strainer preventing reduc- 
tion to be made quick enough to close the feed 
groove in triple; leaky cylinder; and sometimes 
the supply port in the triple valve seat becomes 
clogged up, preventing the auxiliary pressure 
from getting into the cylinder. It has happened 
that the supply pipe in the auxiliary of freight 
equipments has become clogged so that no air 
can get into the brake cylinder, but this is very 
rare. 

Failure to release may be caused by not raising 
the trainpipe pressure above the auxiliary pres- 



200 MODERN AIR-BRAKE PRACTICE 

sure quick enough, as the pressure will equalize 
and fail to move the slide valve if the triple pis- 
ton packing ring is badly worn or gummed up, 
or if the strainer is clogged and retards the flow 
of air, either of which will cause the brake to 
remain set. This frequently happens after an 
emergency application, for as the auxiliary pres- 
sure is then very high, it is necessary that the 
trainpipe pressure should be raised suddenly 
against the plain side of the triple piston, other- 
wise a leak by the packing ring would allow the 
auxiliary to charge without releasing the brake, 
and as a consequence the wheels would be slid, 
or bursted, or a drawhead pulled out. If the 
retainer is turned up, or any dirt clogs in the 
retainer pipe, or should port h in the triple valve 
seat become clogged, the brake cannot be re- 
leased from the engine, and must be bled off by 
letting the air escape through the auxiliary 
release valve, unless the car is equipped with a 
release signal, when it can be used to let the 
brake off. But when a car is not so equipped, 
and should the auxiliary release valve become 
clogged before the triple moves to release posi- 
tion, take out the drain plug in the auxiliary. 
Should the hand brake be set, on a freight car, 
the push rod would not follow the piston back 



ITS USE AND ABUSE 201 

when the air was released, nor if the brake rig- 
ging was caught on a bolt head, or anything. A 
great amount of oil on the slide valve seat will 
prevent a brake being bled off on a detached 
car, as the oil forms a suction so that the cylinder 
pressure can't lift the slide valve to let the air 
out. 

Blow at the triple exhaust, or at the retainer, is 
caused by a leak from either the auxiliary or 
trainpipe side of the triple piston, and may be 
that the slide valve is off its seat, or the gasket 
between the triple and auxiliary may be leaking, 
either of which would be a leak from the aux- 
iliary side of the piston; sometimes, on freight 
cars only, the blow may be caused by a leak in 
the supply pipe (b) between the triple and brake 
cylinder, but this is rare; a blow from the train- 
pipe side on the triple piston would be caused 
by a leak under the em.ergency valve, or there 
may be a leak by check gasket 14. To tell 
where the blow is coming from, cut the brake 
out and if it sets itself the leak is from the train- 
pipe side of the triple piston; if the brake don't 
set when you cut it out, the trouble is an aux- 
iliary leak, and to tell if it is the triple gasket or 
the slide valve, cut the brake in and make a 
reduction on the trainpipe, and if the blow stops 



202 MODERN AIR-BRAKE PRACTICE 

while the brake is set but starts again when the 
brake is released, it is the gaskej:,but if the blow 
continues while the brake is set or released the 
slide valve is causing the trouble. 

Quick action, or going into emergency when only 
a service application was made, is caused by 
either a sticky triple, weak or broken graduating 
spring, or broken graduating valve pin. The 
latter trouble and a sticky triple both act alike, 
for on the first light reduction, if it is a sticky 
triple, the slide valve fails to move and open the 
port into the brake cylinder, and a broken pin 
would prevent the graduating valve from unseat- 
ing, and in either case when the second reduc- 
tion was made the graduating spring could not 
prevent the triple from going to emergency 
position. This action would be the same no 
matter in what part of the train the defective 
triple was located, but if the emergency was 
caused by a weak or broken graduating spring it 
would have to be within seven cars from the 
engine, and would show itself on the first light 
reduction. To find which car it is, cut out a part 
of the train and have the engineer make a very 
light reduction, and if you find a brake not set, 
watch it while the second reduction is being 
made and you will see it fly on, when of course 



ITS USE AND ABUSE 



203 



you will cut it out. If you cut a part of the train 
out and the brakes fail to go in the emergency, 
you know that the trouble is not in that part of 
the train, when you will cut in more cars and try 
again, until you find the bad triple. When a 
train is equipped with the release signal it is not 
necessary to cut out a part of the train to find 
the "kicker," as a five-pound reduction will cause 
all the good brakes to show a portion of their 
signal, and the bad brake will show no signal 
until the second light reduction, when it will fly 
into the emergency. This can be seen from the 
ground or on the top of a freight train. 

Eight-mch Pump. Where the same defect is 
possible in the 9>^ as in the eight-inch pump, it 
will be explained under the 9>^-inch pump. 

If the stem of the reversing piston gets broken 
the pump will sometimes fail to reverse, until 
the piston is jarred down again by lightly tap- 
ping over the cap nut. 

If the stop pin becomes broken the main valve 
will drop down and allow the packing ring of 
the small piston to catch and prevent the pump 
from reversing. 

Should the packing rings on either of the 
main valve pistons, or the reversing piston, 
become so badly worn as to allow free passage 



204 MODERN AIR-BRAKE PRACTICE 

of steam, the pump would not work, and if suffi- 
cient oil does not reach the reversing piston the 
pump is liable to stop. 

Nine and One-half Inch Pump. Constant 
attention and careful management is required 
to keep an air pump in proper working order. 
It is always best to work a pump to its proper 
capacity, but it ruins it to overwork it. Your 
pump is your best friend, so take care of it. 

Pump Running Hot. This may be caused 
from leaky packing rings on the main air pis- 
ton; the piston-rod packing being too tight; not 
enough lift to the discharge valves; choked air 
passages or choked discharge pipe; leaky dis- 
charge valves, too small a main reservoir with 
long train, and fast running. To prevent chok- 
ing up air passages or discharge pipe, or causing 
valves to leak don't use too much oil in the air 
cylinder, and never allow it to be sucked through 
the air inlet. To prevent overheating never run 
the pump faster than sixty full strokes a minute, 
and never run it with leaky valves or packing 
rings. 

To test for leaky disc hai^ge valves, pump up to 
ninety pounds in the main reservoir and shut off 
the pump, then open the oil cup and hold your 
finger over it, and if top discharge valve is leak- 



ITS USE AND ABUSE 205 

ing the air will blow out continuously. For test- 
ing bottom discharge valve remove bottom plug. 
The plug should be removed before making oil- 
cup test, as a leaky bottom valve and leaking 
packing rings would let air blow by the piston. 

To test for leaky packing rings^ on the air 
piston, open the oil cup, run the pump about 
forty-five strokes a minute, and if they leak you 
will feel a gush of air through the oil cup as the 
piston makes the down-stroke. 

Jiggling, or dancing, of the main piston is usu- 
ally caused by too much oil getting under the 
seat of the reversing valve. To take the valve 
out shut off the pump until you get the cap nut 
off, then give it enough steam to raise the pis- 
ton, when you can catch the valve. In putting 
it back be sure you get the groove over the 
guide pin. A bent reversing valve stem will 
sometimes catch on the reversing plate, or the 
latter, having a burr on it, will cause the pump 
to jiggle. 

Pounding may be caused by any of the follow- 
ing defects: Too much lift in the air valves; 
pump loose from frame or frame loose from 
boiler; a worn shoulder on reversing valve not 
allowing piston to reverse quick enough; bot- 
tom end of piston rod worn too far into piston 



2o6 MODERN AIR-BRAKE PRACTICE 

head, which allows piston to strike before re- 
versing; nuts loose on main piston. If the 
pump is started up fast it will pound if the con- 
densation is not drained from the steam end, or 
if there is no air cushion for the piston to strike 
against. 

The Eleven-inch Pumpy being made after the 
same pattern as the nine-inch pump, the same 
rules will apply to both pumps. 

Pump Governor. If the governor don't shut 
off at all and the diaphragm valve port is not 
closed, it is because the pressure has equalized 
on both sides of the air valve, and the vent port 
and waste pipe need to be opened. If the gov- 
ernor shuts off at a low pressure, it is either 
because the regulating spring is too loose, or the 
diaphragm valve dirty or battered so it won't 
seat, or the valve has been filed off too short so 
it can't seat. 

The Gauge. If, with the brake valve in full 
release, the red hand shows less than the black 
hand, it is because the gauge pipes have been 
crossed or the hands have become twisted on 
the pinion. 

The gauge should be tested once a month by 
attaching a test gauge to the trainpipe hose on 
the tender, and placing the brake valve in full 



ITS USE AND ABUSE 207 

release for the red hand and in running position 
for the black hand. 

Engineer s Brake Valve. The only thing that 
can get wrong with a brake valve is a leak some- 
where which will let the pressures run together 
or escape to the atmosphere. 

Pressures Equalize in Running Position. If the 
handle is in running position and both hands 
show the same pressure, the trouble is one of 
three things: either the body gasket, rotary or 
feed valve is leaking. To tell which it is, place 
the handle in service position, and if the body 
gasket is cracked so that main reservoir pres- 
sure flows into cavity D as fast as it passes out 
of the preliminary exhaust, there will be no dis- 
charge from the trainpipe exhaust, and the 
brakes will not set. If the brakes do apply in 
service position, but release when the handle is 
brought to lap, the trouble is a leaky rotary. 
But if the brakes apply in service and remain set 
on lap, and when the handle is again brought to 
running position the pressures again equalize at 
main reservoir pressure, the feed valve needs 
attention. If it is a D-8 brake valve, any one of 
these leaks will allow the governor to shut off 
the pump at seventy pounds, as the governor is 
controlled by trainpipe pressure. In making 



: j8 modern AIR-BRAKE PRACTICE 

{.hese tests the angle-cock behind the tender 
must be closed, as they cannot be satisfactorily 
made if the train brakes are cut in. 

To test if the supply valve of the feed valve is 
leaky, draw off all trainpipe pressure, lap the 
valve and remove the diaphragm piston, place 
the handle on running position and if the supply 
valve leaks you will feel the air blowing out by 
holding your finger under the valve. If no blow 
is felt, the trouble is either in the gasket between 
the feed valve and brake valve, or else the rub- 
ber diaphragm buckles on account of the spring 
box being screwed up too tight. If it is a new 
slide valve feed valve, the trouble may be caused 
by spring 58 being gone, or the small valve 59 
having a bad seat or too short. 

Never oil any part of the old style feed valve, 
and use only high grade machine oil for the 
rotary and the slide valve of the new style feed- 
valve. 

Blow at Trainpipe Exhaust, This is caused 
either by a leak from cavity D or its connection 
with the little drum or black hand of the gauge, 
or dirt under the seat of the equalizing dis- 
charge valve If it is dirt causing the blow, it 
can generally be knocked out by closing the cut- 
out cock under the brake valve and making a 



ITS USE AND ABUSE 209 

reduction of about fifteen pounds and then 
throwing the handle to full release, which will 
cause the short trainpipe temporarily to have a 
higher pressure than cavity D, and of course the 
discharge valve is forced up and the air rushes 
out the trainpipe exhaust and blows the dirt out. 
After trying this and the blow continues, then 
look over the pipe connections. 

If the pipe to the little drum gets broken, plug 
it up and also the trainpipe exhaust and use the 
emergency position in making an application; 
but be very careful to place the handle gradually 
on emergency, and just as carefully bring it back 
to lap, to prevent releasing the brakes by the 
surging of the air. 

Failure to open the trainpipe exhaust when 
the handle is placed in service position, is on 
account of the discharge valve not raising. This 
may be due either to a broken body gasket, let- 
ting main reservoir pressure into cavity D, or 
the packing ring around the discharge valve 
may be letting the trainpipe pressure up on top 
of it. To tell which is causing the trouble, lap 
the brake valve, and if it is the body gasket, the 
trainpipe and main reservoir pressure will equal- 
ize. 

Whistle Signal. A leak in the signal pipe will 



210 MODERN AIR-BRAKE PRACTICE 

cause the whistle to blow. If the supply valve 
of the reducing valve leaks and allows main 
reservoir pressure to equalize with the signal 
pipe, whenever a trainpipe reduction is made 
and the brakes released, the whistle will blow, 
because the main reservoir air going into the 
trainpipe allows the signal pipe air to flow back 
into the main reservoir, which thus makes a reduc- 
tion on the signal pipe and blows the whistle. 

If the whistle fails to respond it is more than 
likely on account of the rubber diaphragm in the 
signal valve being baggy, or the whistle needs 
adjusting, or it is cut out at the reducing valve, 
or an angle-cock is turned. 

If more than one blast is heard when but one 
pull was made, it may be that the diaphragm 
stem needs filing off to allow it to drop further 
down, or there may be dirt holding it up. 

Should the signal pipe fail to charge up it is 
either cut out at the reducing valve or there is 
some dirt lodged in the small opening which 
admits the main reservoir pressure into the 
reducing valve. 

When releasing brakes on a passenger train, 
if the whistle blows it is because the reducing 
valve is letting the signal pipe air back into the 
main reservoir. 



ITS USE AND ABUSE 211 

The engine air gauge can be used in setting the 
reducing valve by drawing the main reservoir 
pressure down to forty pounds, and slacking off 
the regulating spring until the whistle fails to 
blow when the main reservoir pressure is 
reduced below forty pounds. 



QUESTIONS AND ANSWERS TO SEC- 
TION II 

THE CAUSE OF AIR-BRAKE DEFECTS AND HOW TO 
DETECT AND REMEDY THEM 

The following questions will start with the 
engine equipment and be carried right through 
the train. 

45. What effect is produced by leaky packing 
rings in the air end of the pump? 

Ans. — It prevents the pump from producing 
the proper amount of air within the required 
time and causes it to run hot, for the reason that 
if the packing rings are leaking, on the down- 
stroke of the pump the air which is being com- 
pressed in the lower end of the cylinder would 
be forced to the upper end and prevent the 
receiving valve from letting in the required 
amount of fresh air, thereby lowering the effi- 
ciency of the pump. The same action will cause 
the pump to run hot for the reason that on a 
warm summer's day the air in a pump working 
against a ninety-pound pressure in the main 

reservoir is raised to a temperature of 550 

212 



ITS USE AND ABUSE 



213 



degrees, and naturally if the free air is satu- 
rated with a portion of the compressed air which 
is already made hot by compression, it follows 
that a second compression of it greatly increases 
the temperature, thereby causing the pump to 
run hot. 

46. How should you test for leaky packing 
rings in the pump? 

Ans. — First ascertain if the discharge valves 
are leaking, which is done by shutting off the 
steam to the pump and opening the oil cup and 
removing the bottom plug, and holding your 
finger slightly above the oil cup to see if any air 
is blowing out. If the air blows out of the oil 
cup the top discharge valve is leaking, and if it 
blows out of the bottom plug hole the lower dis- 
charge valve is leaking. If no blow is felt either 
at the oil hole or plug hole, then replace the 
plug, leave the oil cup open and start up the 
pump at about forty strokes a minute, and if 
the packing rings are leaking you will feel a 
gush of air through the oil hole as the pump 
makes the down-stroke. 

47. What will cause a pump to jiggle or 
dance? 

Ans. — Too much oil getting under the seat of 
the reversing valve, or if the reversing valve 



214 MODERN AIR-BRAKE PRACTICE 

stem catches on the reversing plate, or if the 
reversing plate has a burr on it, it has a chance 
to jiggle. 

48. What will cause a pump to pound? 

Ans. — Too much lift in the air valves; pump 
being loose from the frame, or frame loose from 
the boiler; a worn shoulder on the reversing 
valve which would prevent the piston from 
reversing quick enough; the bottom end of the 
piston-rod worn too far into the piston head will 
allow the piston to strike before reversing; loose 
nuts on the main piston; or if the pump is 
started to running fast before the condensation 
has been properly drained, or if there is no air 
cushion for the piston to strike against. 

49. When should the air end of the pump be 
oiled? 

Ans. — Every time the engine is started on a 
trip and oftener if required, but great care must 
be taken not to get too much oil in the air end 
as it will cause the valves to gum up and make 
the pump run hot. 

50. What kind of oil should be used in the 
pump? 

Ans. — Cylinder oil* engine oil should never be 
used in the pump. 

51. How often should a pump be cleaned? 



ITS USE AND ABUSE 215 

Ans. — At least every six months by running a 
solution of potash through it, and in doing so 
the connections between the main reservoir and 
the tender should be broken so that no potash 
can work into the brake equipment. 

52. If the trainpipe and main reservoir pres- 
sure equilizes while the handle of the brake 
valve is in running position, what might be caus- 
ing the leak? 

Ans. — Any one of three things; either the 
rotary valve, the body gasket, or feed-valve 
attachment. To tell which it is, place the 
handle in service position and if the body gasket 
is cracked so that main reservoir pressure flows 
into cavity D as fast as it passes out of the pre- 
liminary exhaust, there will be no discharge 
from the trainpipe exhaust and the brakes will 
not set. If the brakes apply in service position, 
but release when the handle is brought to lap, 
the trouble is a leaky rotary. But if the brakes 
apply on service and remain set on lap, and 
when the handle is again brought to running 
position the pressure again equalizes, it is the 
feed valve that needs attention. To tell if it is 
the supply valve of the feed valve, draw off all 
trainpipe pressure, lap the valve, and remove 
the diaphragm piston, place the handle in run- 



2i6 MODERN AIR-BRAKE PRACTICE 

ning position, and if the supply valve leaks you 
will feel the air blowing out by holding your 
finger under the valve. If no blow is felt the 
trouble is either in the gasket between the feed 
valve and the brake valve, or else the diaphragm 
buckles on account of the spring box being 
screwed up too tight. If it is a new slide valve 
feed valve, the trouble may be caused by spring 
58 being gone, or the small supply valve 59 hav- 
ing a bad seat, or else too short. If you are 
testing a D-8 brake valve, any one of these leaks 
will allow the governor to shut off the pump at 
seventy pounds for the reason that the governor 
is controlled by trainpipe pressure with this kind 
of a valve. 

53. Is there anything else that would prevent 
the trainpipe exhaust from opening in service 
position besides a cracked body gasket? 

Ans. — Yes. If the packing ring around the 
equalizing valve leaks badly it will allow the 
trainpipe pressure to get on top of it as fast as 
the preliminary exhaust port lets the air out of 
cavity D. 

54. Should you lose your equalizing reservoir, 
or damage it so that it leaked, how would you 
handle your train? 

Ans. — Plug the trainpipe exhaust and also the 



ITS USE AND ABUSE 217 

pipe leading to the equalizing reservoir and use 
the emergency position for applying brakes, but 
be very careful to go slowly to the emergency 
position and also slow in bringing the handle to 
lap. 

55. If the pump governor doesn't shut off at 
all, what is the trouble? 

Ans. — It is because the pressure has equalized 
on both sides of the air valve, and the vent port 
and waste pipe need to be opened. If it shuts 
off at a low pressure it is caused by the regu- 
lating spring being too loose or the diaphragm 
valve is dirty or battered so that it wont seat, or 
else the valve has been filed off so that it is too 
short to seat. 

56. What would cause the black hand of the 
gauge to show more pressure than the red hand? 

Ans. — Either the pipes have been crossed or 
the hands have become twisted on the pinion, or 
stuck. 

57. What will cause the whistle to blow when 
the brake valve handle is thrown to full release? 

Ans. — A leak in the supply valve in the 
reducing valve, which allows the signal whistle 
pressure to flow back into the main reservoir. 

58. What will prevent the whistle from 
responding when the whistle cord is pulled? 



2i8 MODERN AIR-BRAKE PRACTICE 

Ans. — The rubber diaphragm in the signal 
valve being baggy, or the whistle not being 
properly adjusted. Of course, if it is cut out at 
the reducing valve, or a cut-out cock is turned it 
will not whistle. 

59. What will cause a blow at the triple 
exhaust? 

Ans. — A leak from either the auxiliary or 
trainpipe side of the triple piston. 

60. How many places are there at which such 
a leak might occur? 

Ans. — Four. Under the slide valve, or the 
gasket between the triple and auxiliary, under 
the emergency valve, or by check gasket 14. 
To tell where the blow is coming from, cut the 
brake out and if it sets itself the leak is from 
the trainpipe side of the piston; if the brake 
don't set when you cut it out the trouble is an 
auxiliary leak, and to tell if it is the triple gasket 
or the slide valve, cut the brake in and make a 
trainpipe reduction, and if the blow stops while 
the brake is set but starts again when the brake 
is released it is the gasket; but if the blow con- 
tinues while the brake is either set or released, it 
is the slide valve that is causing the trouble. 

61. What causes a brake to fly into the emer- 
gency when a service application is made? 



ITS USE AND ABUSE 2ig 

Ans. — It is either because of a sticky triple, 
weak or broken graduating spring, or broken 
graduating valve pin. The latter trouble and a 
sticky triple both act alike, for on the first light 
reduction if it is a sticky triple, the slide valve 
fails to move, and consequently no air gets into 
the brake cylinder, and a broken pin would pre- 
vent the graduating valve from unseating, so 
that in either case, when the second reduction 
was made the graduating spring could not pre- 
vent the full travel of the triple piston, and the 
brake would, of course, go into the emergency. 
The action would be the same no matter in what 
part of the train the defective triple was located, 
but a weak or broken graduating spring would 
cause an emergency application only when the 
defect is within seven cars from the engine, in 
which case the brakes would fly into emergency 
on the first light reduction. 



SECTION III 



CHAPTER IV 

THE PHILOSOPHY OF AIR-BRAKE HANDLING — RULES 
AND TABLES FOR COMPUTING BRAKE POWER- 
BRAKE LEVERAGE — EQUALIZATION OF 
PRESSURE, ETC. — SIZES OF CYLIN- 
DERS AND RESERVOIRS — TEST- 
ING AND INSPECTION OF 
AIR BRAKES^ — ETC. 

After an engineer has learned the name and 
duty of every part of the air-brake equipment, 
his knowledge is of but little use either to him- 
self or his employers unless he also learns the 
philosophy of air brake handling. 

What is meant by the philosophy of air-brake 
handling is a clear and definite understanding of 
the effects produced by different volumes and 
pressures when the varying conditions of the 
brake equipment, track, load, grade and speed 
are taken into account. 

One of the first things an engineer should 
learn is the value of maintaining correct stand- 



ITS USE AND ABUSE 221 

ards of pressures in the different parts of the 
equipment. 

For example, the cars in a freight train are 
braked to only seventy per cent of their light 
weight, which means that with the quick-action 
triples the leverage is arranged with the under- 
standing that the brake cylinder must contain a 
pressure of sixty pounds to the square inch in 
order to produce a brake power of seventy per 
cent. This means that an emergency applica- 
tion is required to be made, and the piston- 
travel not over eight inches, if the full seventy 
per cent is to be gotten. 

Therefore, if a train of fifty cars, with every- 
thing in first class condition, was running forty 
miles an hour and the brakes were thrown on 
with an emergency application, it would have to 
run about 675 feet, or an eighth of a mile, before 
coming to a stop. This is because the stopping 
power is only equal to seventy per cent of the 
weight to be stopped. If these same fifty cars 
were all loaded to their capacity of 60,000 
pounds each, the per cent of brake power to the 
weignt to be stopped would be entirely changed, 
for with fifty cars of 30,000 pounds weight each, 
the total weight to be stopped would be 1,500,000 
pounds, and if the brakes were properly adjusted 



222 MODERN AIR-BRAKE PRACTICE 

there would be an available stopping power, of 
1,050,000 pounds, but when the cars are loaded 
the weight to be stopped is 4,500,000 pounds, and 
with an emergency application you have only 
got a stopping power equal to twenty-three and 
a third per cent of the weight, and as it requires 
a greater force to check the momentum of a 
heavy weight than it does for a light one, the 
loaded cars will run a considerable distance 
further than the empty cars would before stop- 
ping. 

The reason the percentage of stopping dis- 
tance is not greater in proportion to the 
decreased brake power is because when once 
the momentum is checked the force of gravity 
causes the heavy weight to settle quicker than a 
light weight. It is on this account that a train 
running twenty miles an hour can be stopped in 
a much shorter distance than one running forty 
miles an hour. At twenty miles an hour a fifty- 
car train can be stopped in less than 200 feet. 

When making a service application the pres- 
sure in the brake cylinder is only fifty pounds to 
the square inch, and the brake power is thus 
reduced one-sixth, consequently there is only a 
fraction over fifty-eight per cent available stop- 
ping power on a light car, and only about nine- 



ITS USE AND ABUSE 223 

teen per cent on a loaded one, but if the brake 
shoes are hung from the body of the car the pis- 
ton-travel will be increased from one to three 
inches when the car is loaded, as the shoes 
strike the wheels lower down when loaded than 
empty. This means that if such a car was brak- 
ing to seventy per cent light it would only be 
braking to a fraction over fourteen per cent 
loaded, and if the piston-travel was over eight 
inches when the car was empty the brake power 
would be still further reduced. 

If the piston was allowed to travel its full 
stroke, there would be no brake power exerted 
against the wheels, as all the force would be 
against the cylinder head. 

While these facts should be self-evident to all 
enginemen and trainmen, a great number of 
them, however, seem to think if the leaks in the 
trainpipe are stopped that the brakes are all 
right. 

It should never be lost sight of that whenever 
you change the piston-travel or load you also^ 
change the per cent of brake power. 

An example of the stopping distance required 
for a heavy car, as compared with a lighter one, 
was recently given when a Pullman car weighing 
about 100,000 pounds was "kicked" off while run- 



224 MODERN AIR-BRAKE PRACTICE 

ning thirty miles an hour, and it stopped in 416 
feet, while a coach weighing about 60,000 pounds 
stopped in 202 feet after being kicked off at 
thirty miles an hour. In both cases the braking 
power was ninety per cent of the weight, but 
there was a difference of forty per cent in the 
weight of the cars. 

Train Handling. While different conditions 
require different handling of trains, there are, 
however, two distinct points to be remembered 
as regards the difference between stopping a 
freight train and a passenger train. 

In stopping a passenger train running twenty- 
five miles an hour or over, two applications 
should be made, and the final release made just 
before the train comes to a stop. If the stop is 
made on a grade, reapply the brakes to prevent 
drifting. 

In stopping a freight train but one application 
should be made, and never release until the train 
comes to a standstill, or you are very liable to 
pull your train in two. 

An "application" is from the time the first 
reduction is made until the brakes are released, 
several "reductions" can be made during one 
application. 

Why two applications should be made with a 



ITS USE AND ABUSE 225 

passenger train is, first, because the speed has to 
be reduced before the stop can be made, and, 
second, the train should be absolutely under 
control in approaching a station, as something 
or some one may be on the track, and if the 
engineer was making a 'one application stop" 
the auxiliaries and cylinders would have equal- 
ized some distance back of the actual stopping 
place, and the train would drift to the usual 
place in spite of anything the engineer could 
do. 

In making a two application stop the first 
reduction should be about ten pounds, followed 
in a few seconds by about five pounds, and again, 
in a few seconds, by five more, which will equal- 
ize the pressures. By this time the train is only 
running about fifteen or eighteen miles an hour, 
and you are nearly to the station, so you must 
now place the handle in full release just long 
enough to be sure that all brakes are off, and 
bring it to lap. This prevents the trainpipe 
pressure from becoming higher than that in the 
auxiliaries, and when you begin to make the 
actual stop a reduction of seven or eight pounds 
will cause the triples to move at once, and again 
set the brakes. When you feel that this reduc- 
tion has produced the desired effect, make 



226 MODERN AIR-BRAKE PRACTICE 

another of four or five pounds and let the train 
drift to the usual place, and release just before 
it stops, which allows the trucks to right them- 
selves, and no one is jerked off his feet in the 
coaches. 

By making two applications you get two shots 
out of each auxiliary, and, besides, after releas- 
ing the first time, you have a chance to get the 
added twenty per cent of brake power by using 
the emergency, if you have to; whereas if you 
were making the stop with one application you 
could never get more than a full service applica- 
tion after a ten-pound reduction, even if you 
used the emergency, which, of course, you 
should always do in case of danger. 

With the high-speed brake a train can be 
stopped in about thirty per cent less distance 
than it can with a quick-action brake. For 
instance, a train running forty-five miles an 
hour can be stopped in 560 feet with the high- 
speed brake as against 710 feet with the quick- 
action brake. Consequently a train running 
sixty miles an hour can be stopped in 1,060 feet 
with the high-speed brake, making a net gain of 
300 feet over a stop made with the quick-action 
brake, which requires 1,360 feet within which to 
stop a train running sixty miles an hour. 



ITS USE AND ABUSE 227 

Two applications should always be made with 
the high-speed brake in making a stop, but the 
initial reduction can be fifteen pounds instead of 
ten pounds, as would be proper when using the 
automatic brake. In making a ten or fifteen- 
pound reduction with the high-speed brake from 
iio-pound trainpipe pressure, the same cylinder 
pressure is produced as there would be if the 
same reduction were made with the automatic 
brake from seventy-pound trainpipe pressure, 
provided the piston-travel is the same. But, 
after the brake cylinder pressure has been raised 
with the high-speed brake to the point at which 
equalization would take place with the auto- 
matic brake, then any further reduction of the 
trainpipe pressure with the high-speed brake 
would raise the brake cylinder pressure accord- 
ingly. For example, an emergency application 
made with the automatic brake would produce a 
brake cylinder pressure of sixty pounds, whereas 
with the high-speed brake an emergency appli- 
cation will produce a brake cylinder pressure of 
about eighty-eight pounds. As this pressure is 
equivalent to a brake power of 130 per cent of 
the weight of the car, you will understand why 
it is necessary to have an automatic reducing 
valve to let the high pressure escape, as the 



228 MODERN AIR-BRAKE PRACTICE 

train slows down, in order to prevent wheel 
sliding. 

If the auxiliary and trainpipe pressure (after 
making a reduction) equalizes at any point above 
sixty pounds, just as soon as the auxiliary pres- 
sure gets a fraction lower than the trainpipe 
pressure the triple will automatically lap itself, 
so that while the brake cylinder, owing to the 
reducing valve, may only have sixty pounds in 
it there might still be seventy-five pounds, or 
more, in the auxiliary reservoir and trainpipe. 
Therefore, with the high-speed brake equipment 
an engineer can make two full service reductions 
of twenty pounds and release his brakes and 
still have seventy pounds pressure left in the 
auxiliaries with which to stop, if necessary, 
without having to recharge. 

Owing to the high pressure contained in the 
auxiliary reservoir with the high-speed brake 
the air is forced into the brake cylinder more 
quickly than it is with the automatic brake, and 
naturally takes hold quicker. But, as previously 
explained, there is no greater pressure per 
square inch in the brake cylinder from a ten or 
fifteen-pound reduction with the high-speed 
brake than there would be if made with the 
automatic brake. 



ITS USE AND ABUSE 229 

Handling a freight train is very different from 
handling a passenger train, and when handling 
a freight train the following points should 
always be kept in mind: 

Good driver and tender brakes on the heavy 
class of freight engines are equal to the brake 
power furnished by six or seven 30,000-pound 
cars. 

Always listen to the blow from the trainpipe 
exhaust when making a service application, as 
by the length of the blow you can tell the length 
of your trainpipe. This little item may save 
your life, as there are many ways for an angle- 
cock to become closed. 

Always insist on having your train brakes 
carefully tested, and their condition and num- 
ber reported to you before leaving a terminal, 
or where any change has been made in the 
train. 

Always lap your brake valve if the brakes 
apply suddenly without any apparent cause, as a 
hose may have bursted or a conductor's valve 
opened, and you will need all your m.ain reser- 
voir pressure to release and recharge 

Always close the steam-throttle in case of a 
break-in-two, for with a partially equipped train 
the non-air cars will only hit the head end that 



230 MODERN AIR-BRAKE PRACTICE 

much harder if you try to pull away, as the air 
brakes will stop you anyway. 

Never reverse an engine after applying the 
brakes, as good engine brakes will hold con- 
siderably more than reversing the engine, and 
besides, it will flatten the tires if you reverse 
with the brakes set. 

In using sand, be sure to get it upon the rail 
before the speed of the train has been materially 
reduced, or it will slide the wheels, and if sand is 
used while the wheels are sliding it is certain to 
put bad spots on them. 

In making a service application you must be 
governed by circumstances, as regards speed, 
load and grade, but never make less than a five- 
pound reduction to start with, as less than that 
will not push the brake piston out past the leak- 
age groove. Ordinarily from five to seven 
pounds will be right, but you must always wait a 
few seconds between the first and second reduc- 
tions to allow the slack to run out. 

In handling loaded trains on heavy grades, it 
is always best to make about a ten-pound reduc- 
tion to start with. (See "Train handling on 
heavy grades.") 

Watch the air gauge as closely as possible. 

Never make over a twenty-five pound reduc- 



ITS USE AND ABUSE 231 

tion in service applications, for with correct pis- 
ton-travel a twenty-pound reduction will equalize 
the pressures, and any further reduction is a 
waste of air. 

Always make a running test with a passenger 
train, and also with a freight train where track 
conditions will permit it. Some hobo may turn 
an angle-cock on you. 

In all cases of emergency throw the handle to 
emergency position and leave it there until the 
train comes to a standstill. But with a passen- 
ger train the brakes may be released while run- 
ning if the danger has been removed. 

Releasing the Brakes. Never try to release 
brakes in running position, with the mistaken 
idea that you will "just kick off a few," for it is 
just this kind of foolishness that causes many 
flat and broken wheels. When the brake valve 
is in running position the trainpipe pressure 
raises comparatively slow, and if there should be 
any leaky triple piston packing rings the train- 
pipe and auxiliary pressures will equalize with- 
out moving the slidevalve, and consequently 
the brakes on all such cars will stick, and on 
poor rail the wheels on such cars may catch 
and slide while going slow, or if a brake sticks 
for any considerable time it will overheat the 



232 



MODERN AIR-BRAKE PRACTICE 



wheel and cause it to burst and wreck the 
train. 

The amount of money paid out annually by 
railroad companies on account of "brakes stick- 
ing" is something enormous. The money paid 
out on account of doubling hills from brakes 
sticking would make a nice fortune. 

To release brakes, always use full release posi- 
tion, no matter how long the train is. 

Never open the throttle just after releasing 
brakes on a freight train, but allow the slack to 
adjust itself first. If you don't, you are almost 
sure to pull out a draw head and part your 
train. 

To insure a prompt release, when coupling 
onto an empty or partially charged train, always 
make about a fifteen-pound reduction and hold 
the handle on lap until the trainman has made 
the coupling and opened both angle-cocks. 
Some engineers are always complaining about 
their tender brake sticking, when the proba- 
bility is they have allowed the auxiliary to 
charge up to seventy pounds, and when the 
trainman opens the angle-cock between the ten- 
der and train it naturally reduces the trainpipe 
pressure and sets the brake on the tender, and 
as the volume of space in the trainpipe prevents 



ITS USE AND ABUSE 233 

a quick raising of the pressure, and as a very 
slight leak by the triple piston packing ring will 
allow the pressures to equalize, it is easy to 
understand why the tender brake sticks. 

Failure to release brakes is commonly caused 
by not carrying sufficient excess pressure, for 
unless the trainpipe pressure is raised suddenly 
the slight leaks by the packing rings in the 
triples will cause the brakes to stick, for as the 
head triples are moved first, the feed grooves 
in the triples allow the trainpipe pressure to 
become lower every time a brake is released, so 
that on a long train the pressure would become 
so low as it neared the rear end that it would 
not be strong enough to force the triples to 
release position. Sometimes a brake can be 
released by making another heavy reduction, 
which changes the relation between the train- 
pipe and main reservoir pressures so that the 
excess thus created will give the triple a ham- 
mer blow and drive it to release position when 
the handle is thrown to full release. But, of 
course, if the brake is sticking on account of a 
leaky packing ring it would have to be bled off, 
either by the auxiliary bleed cock or the release- 
signal valve. 

In taking ivater. with a freight train, it is 



234 MODERN AIR-BRAKE PRACTICE 

always best to stop short of the water plug, cut 
off, and run up with the engine alone. 

hi setting out cars, always apply the brakes 
before the train is cut, because there can be no 
danger then of pulling out with an angle-cock 
closed against you. 

Train Handling on Heavy Grades, Trains are 
frequently stalled on heavy grades because the 
engineer keeps throwing the handle of the brake 
valve to full release and then bringing it back to 
running position. By doing this he soon gets 
the trainpipe charged higher than what the feed 
valve is set for, and then, in running position, 
the brakes are sure to creep on, for the trainpipe 
pressure must be reduced before the feed valve 
will open to admit main reservoir pressure. 

A heavy initial reduction is proper with loaded 
trains on heavy grades, because a certain 
amount of the brake power is necessary to over- 
come the ''drop" or downward movement caused 
by gravity, which materially reduces the amount 
left for holding the train at a certain speed. 

As soon as the train passes a summit the 
brakes should be applied, in order to know for a 
certainty what they are capable of doing. By 
waiting until the train is well under way before 
applying the brakes is very liable to cause a 



ITS USE AND ABUSE 235 

runaway, as the trainmen have a poor chance of 
stopping it by hand brakes, should the occasion 
arise. The man who is not afraid to call for 
hand brakes when he thinks there are not enough 
good air brakes to hold the train, is much safer 
for the railroad company than the fellow who is 
afraid to do so because the train crew will think 
"he has lost his nerve." 

In descending a grade, always try to keep the 
trainpipe pressure as near standard as possible, 
by recharging as often as may be required, for 
in case a stop has to be made you will need all 
the power you can get. 

Always recharge in full release position. If 
the trainpipe pressure shows up on the gauge to 
be above standard, bring the handle to running 
position for a few seconds to allow it to equalize, 
and then place it on full release just for a second 
to kick off any forward brakes that may have 
set, owing to the auxiliaries on the forward cars 
charging up faster than the others. 

Comparatively slight trainpipe leaks are more 
dangerous on a heavy grade than leaks which 
are readily noticed, for after a light application, 
unless the gauge is watched very close, the 
slight leaks will cause the brakes to continue to 
set until the pressures are equalized, when it 



236 MODERN AIR-BRAKE PRACTICE 

would be impossible to apply them any harder 
should a stop have to be made. 

Hostlers should remember that there are more 
than two positions (emergency and full release) 
on the brake valve. An emergency application 
is only intended to be used when the full brake 
power is required. A full service application is 
only necessary when running at a high rate of 
speed, therefore when handling an engine 
through the yards, make light applications of 
about five pounds to start with, and gradually 
increase the reduction as occasion demands. If 
you are running slow, don't try to use a high 
speed application, as you are very liable to slide 
the wheels. Never use the emergency on the 
turn table. 

TESTING AND INSPECTION OF AIR BRAKES 

No train should ever leave a terminal until 
the brakes have been thoroughly tested and put 
in good order. 

In testing a train^ begin at the rear end and 
close the angle-cock, and, if it is a freight train, 
couple the hose between the caboose and the 
first car, after knocking the hose-couplings 
together to jar out any dirt that may be lodged 
in them, then turn the angle-cocks straight with 



ITS USE AND ABUSE 237 

the pipe; next, see that the brake is cut in at the 
cross-over pipe; examine the retainer to see 
that the handle is turned down, and notice if the 
hand brake is released. Treat every car in the 
train alike, and when you reach the head end, 
before coupling the tender hose, always blow it 
out by opening the angle-cock. 

While the train is being charged up, which 
will take about fifteen minutes, if it is a thirty or 
forty-car train, go over the train and stop all the 
leaks. If a bad blow is found at a triple gasket 
which can't be stopped by tightening the nuts, 
cut the brake out, bleed it and report it on a 
defect card. If the blow is at the hose-coupling, 
and a new gasket does not stop it, drive a small 
sliver of wood, or a match, between the lugs, 
which will force the heads together. Never use 
paper or a nail. 

When the train is charged up and the brakes 
have been set, begin at the front end and exam- 
ine the piston-travel on each car. If a piston is 
found to travel nine inches, or over, mark the 
car so that you will know whether to take up or 
let out the travel, after the engineer has released 
the brakes. 

Should you come to a car where the brake is 
cut in and the auxiliary charged, but the piston 



238 MODERN AIR-BRAKE PRACTICE 

is not out, have the engineer make a further 
reduction to ascertain if the brake "leaked off" 
or "released." If it releases you can hear it 
blow out of the retainer, and if it leaks off the 
air is escaping around the packing leather in the 
cylinder, which usually cannot be heard. In 
either case cut out the brake and report it cor- 
rectly, for if you say it leaked off, the car 
repairer will go after the cylinder leather, and if 
you say it released, he would go after the triple. 

Upon reaching the rear end of the train, sig- 
nal the engineer to release, and then see if every 
car releases properly. 

If a brake has failed to release, examine the 
retainer, and if it is found with the handle turned 
down, and the brake rigging is not caught, cut 
the brake out, bleed it and report it. 

When you come again to any car which you 
had previously marked for changing the piston 
travel, take up or let out the slack by moving 
the truck dead lever forward or back, as the 
case may be, but be sure to take it up at both 
ends of the car alike. 

Having finished inspecting the train, report to 
the engineer the number and condition of the 
brakes in working order. 

When a train is equipped with the release sig- 



ITS USE AND ABUSE 239 

nal you can tell by the action of the signal just 
what the brake is doing and if the piston travel 
is too great. 

BRAKE LEVERAGE 

The subject of brake leverage is a very inter- 
esting one, but as all foundation brakes are sup- 
posed to be carefully figured out by competent 
experts when the car is built, an absolute knowl- 
edge of leverage is not required of enginemen 
or trainmen. I shall, however, explain the 
different kinds of levers and the manner of 
figuring them so that any one can, by a few sim- 
ple calculations, tell if a car or engine is getting 
its proper braking power, and also lay out the 
proper leverage when building new work. 

In order to tell the proper proportion of braice 
levers, or to ascertain what force is being exerted 
at any of the pins, it is necessary to take into 
account two forces and two distances. 

The two forces represent the power applied at 
one pin and the weight lifted by the other pin, 
between which is the fulcrum; the two distances 
are figured from the fulcrum to the applied 
power and from the fulcrum to the weight. 

In every case the applied power multiplied by 
the distance it is from the fulcrum divided by 



240 MODERN AIR-BRAKE PRACTICE 

the distance from the fulcrum to the weight, will 
tell you what the weight is that is being lifted 
by the applied power. 

The point that most bothers the new student 
is to tell where the fulcrum is, but this will come 
all right with a little practice. 

Remember that in figuring leverage you must 
take "proportion" into account. If the applied 
power is proportionately one-third nearer the 
fulcrum than the weight is to the fulcrum, the 
power can only lift a weight equal to one-third 
of its force, and if the opposite is true then the 
power can lift a weight equal to three times its 
force. 

For example, if a lever is forty inches long 
from the centers of the outside holes, and 
another hole is placed ten inches from either 
end, it would be called a one to three lever, for 
when you divide forty into two parts of ten and 
thirty, the result is that one portion is three 
times greater than the other, so that if you 
applied the power at either end and the weight 
at the other, then the fulcrum would be the ten- 
inch hole, and if the power of, say, lOO pounds, was 
nearest the fulcrum, you would multiply loo by 
lo, which would equal i,ooo, and when you divide 
I, GOG by 30 the result would be 33,}i, or one-third 



ITS USE AND ABUSE 241 

of the applied power. This would be called a 
lever of the first kind. 

Now suppose that the power was at the long 
end of the lever, and the weight at the other, 
then the fulcrum would be at the thirty-inch 
hole. So that 100 multiplied by 30 would equal 
3,000, which divided by 10 would equal 300 or 
three times the applied power. This is also a 
lever of the first kind. 

Again, suppose the power was nearest the ten- 
inch hole, and the weight was at the ten-inch 
hole, then the fulcrum would be forty inches 
away from the applied power. In order to tell 
how much weight could now be lifted by the 100 
pounds, you would multiply it by 40, which 
would equal 4,000, divided by 30 would equal the 
weight, 133K pounds, for the reason that the 
fulcrum is three-thirds, or one whole number, 
away from the power, which gives 100 pounds 
lift, and the weight being one-third the distance 
from the power, gives a lift of one-third of the 
applied power, and the two combined equal one 
and one-third the force of the applied power. 
This is called a lever of the second kind, as the 
delivered force or weight is between the fulcrum 
and the applied power. 

The third kind of lever is designated by hav- 



242 MODERN AIR-BRAKE PRACTICE 

ing the applied force between the fulcrum and 
the delivered force, and is explained as follows: 
The applied power is now at the ten-inch hole, 
and the weight is at the end nearest the power, 
which would make the fulcrum at the opposite 
end, or thirty inches from the power. Multiply 
the loo by 30, and you have 3,000 pounds, which 
divided by 40 (the distance the weight is from 
the fulcrum), and you have a lifting force of 
seventy-five pounds; for the reason that the 
applied power is located three-fourths the dis- 
tance from the fulcrum to the weight. If you 
change the weight so that it would be at the 
thirty-inch hole the lifting force at the weight 
end would only be twenty-five pounds, because 
the applied power would then be located at a 
point equal to one-fourth the distance that the 
fulcrum is from the weight. 

Therefore, with a lever of the third kind the 
lifting force is always increased in proportion to 
the distance that the applied power is from the 
fulcrum as the fulcrum is from the total length 
of the lever; in other words, by moving the 
applied power toward the weight increases the 
lifting force and moving the applied power away 
from the weight toward the fulcrum decreases 
the lifting force. 



ITS aSE AND ABUSE 243 

Always remember that the appHed power and 
the weight added together equal the strain at 
the fulcrum. 

Should you wish to design a cylinder lever and 
wanted to know where to place the middle, or 
fulcrum pin, you would proceed as follows: 
Multiply the weight to be moved by the total 
length of the lever, between the two centers of 
the outside holes, and divide it by the applied 
force and weight combined; the result would be 
the distance in inches from the cylinder pin hole 
to the fulcrum. To prove it, multiply the 
applied force by the length, and divide by the 
force and weight combined, which should equal 
the number of inches from the fulcrum to the 
vv^eight pin hole. 

For example, suppose you had an eight-inch 
cylinder, with a quick-action triple, the applied 
power would be 3,000 pounds; now suppose you 
wanted a force of 1,500 pounds on the floating 
lever end of the cylinder lever, which is ^^ 
inches long, you would multiply 3,000 by 33, which 
equals 99,000, now divide this by the required 
force (1,500) and the applied power (3,000) com- 
bined (or 4,500), and you have as a result 22, 
which is the number of inches the hole should 
be from the weight end of the lever which would 



244 MODERN AIR-BRAKE PRACTICE 

make the fulcrum eleven inches from the cylin- 
der end of the lever. Prove this by multiplying 

F 



W'^^ 

F-^ 



a=WJLb or a=Wxi 
F F+W 

w ^ F-\-W 




FULCRUM BETWEEN APPLIED AND DELIVERED FORCES. 




Fyg 

TTxb 
a 

a»HXft or g^^xd 
F }V-F 

& =. ^x o ^ b., Fxd 
TF W-F 

DELIVERED FORCE BETWEEN FULCRUM AND 
APPLIED FORCE. 




■ PTxb 
a 

F F-W 

b ||F- or i)» jTT^ 



APPLIED FORCE BETWEEN FULCRUM AND 
DELIVERED FORCE, 

PLATE NO. 34. — BRAKE LEVEKS. 



ITS USE AND ABUSE 245 

3,000 by II, and dividing by 22, and see if you 
don't get 1,500 as a result. 

Plate 34 illustrates the formula for calculating 
the different kinds of levers. The first kind is 
where the fulcrum is in the middle; the second 
has the weight in the middle, and the third has 
the applied power in the middle. 

The first formula translated into straight Eng- 
lish would read as follows: The weight (W) is 
equal to the applied power (F) multiplied by the 
distance (a) from the power to the fulcrum, 
divided by the distance (d) from the fulcrum to 
the weight. From this you can read the others. 

Plate 35 illustrates the two systems of brake 
levers used on passenger cars, and also the ten- 
der levers. The Hodge system is especially 
indicated as having a floating lever, which the 
Stevens system has not. 

Plate 36 shows a freight equipment of levers 
with the brake shoes attached below the bottom 
rod. The plate shows the result of an emer- 
gency iand a service application. 

RULES FOR CALCULATING BRAKE POWER 

The force exerted upon the piston depends 
upon the size of the cylinder and the air pres- 
sure in the cylinder. 



246 MODERN AIR-BRAKE PRACTICE 

To get the number of pounds push at the pis- 
ton, multiply the number of square inches on the 
piston by the number of pounds pressure per 
square inch on the cylinder. For example, an 




HOOOC 6VBTCM 
^f« BRAKE LEVERS. 



Fig. 




SrcVE_NS ^aTEM 
GAP BRAKE (.CVCnS. 



Fig. 2. 




Fig. 3. 
plate no. 35. — car and tender truck brake levers. 



ITS USE AND ABUSE 247 

eight-inch piston contains fifty square inches, 
which multiplied by fifty, the cylinder pressure, 
would give a push of 2,500 pounds at the end of 
the piston-rod. 

To find the number of square inches on a pis- 
ton, multiply the diameter by itself, and by the 
number thus obtained multiply .7854, and cut off 
the last four figures from the result, and the 
remainder will be the number of square inches. 
For example, 8 times 8 is 64, and .7854 multi- 
plied by 64 equals 50.2656, or 50 inches and 2,656 
ten thousandths of an inch, so you just cut off 
the ten-thousandths, unless they are equal to a 
half number or better, when you count them a 
half, as for instance a ten-inch cylinder would be 
counted as having '/Sj4 square inches. 

A short method is to multiply the diameter oy 
itself, and the result by 11 and divide by 14. 

To find at what pressure the auxiliary would 
equalize with the cylinder, find the number of 
cubic inches contained in the auxiliary by multi- 
plying the number of square inches contained in 
its diameter by its length (minus the concavity 
in the heads), and then multiply the cubic inches 
by the pressure with fifteen pounds added, and 
divide by the combined cubic inch contents of 
the auxiliary and cylinder, and deduct the fifteen 



248 



MODERN AIR-BRAKE PRACTICE 




ITS USE AND ABUSE 249 

pounds which you added, and the result will 
show the point of equalization. 

For example, a freight auxiliary contains 
about 1,620 cubic inches, and the standard pres- 
sure is 70 pounds; to this add 15, which makes 
85, now multiply 1,620 by 85 and you get 137,700. 
An eight-inch cylinder, with eight-inch piston 
travel, contains about 450 cubic inches. The 
cylinder and auxiliary together hold 2,070; now 
divide 137,700 by 2,070 and you get 66 >^, from 
which deduct 15, and the result is 51 K, or the 
pounds pressure at which they equalize. 

The following table gives the force exerted 
upon the pistons of the different sized cylinders 
with pressures of fifty and sixty pounds per 
square inch: 

Size of cylinder, 6" 8" 10" 12" 14" 16" 
50 lbs. pressure, 1,000 2,500 4,000 5,650 7,700 10,059 
60 lbs. pressure, 1,700 3,000 4,700 6,700 9,200 12,050 

SIZES OF AUXILIARY RESERVOIRS WHICH SHOULD BE 

USED WITH DIFFERENT SIZED CYLINDERS, WITH 

THE CUBIC-INCH CAPACITY OF EACH, WITH 

EIGHT - INCH PISTON TRAVEL 

Eight-inch tender and truck cylinders, with 
10x24 auxiliary: Cubic inches of cyHnder, 450. 
Cubic inches of auxiliary, 1,491. 



250 MODERN AIR-BRAKE PRACTICE 

Eight-inch driver brake cylinders, with 10x33 
auxiliary: Cubic inches in auxiliary, 2,050. 

Ten-inch cylinders of all kinds, with 12x33 
auxiliary: Cubic inches in cylinder, 628. Cubic 
inches in auxiliary, 3,030. 

Twelve-inch cylinders of all kinds, with 14x33 
auxiliary: Cubic inches in cylinder, 904. Cubic 
inches in auxiliary, 4,120. 

Fourteen-inch cylinders of all kinds, with 
16x33 auxiliary: Cubic inches in cylinder, 
1,232. Cubic inches in auxiliary, 5,450. 

Sixteen-inch cylinders of all kinds, with 16x42 
auxiliary: Cubic inches in cylinder, 1,600. Cubic 
inches in auxiliary, 7,163. 

CYLINDER PISTONS AND AUXILIARY DIAMETERS 

The following tables show the number of 

square inches on the different sized pistons, and 

inside diameter of auxiliary resevoirs: 

8-inch cylinder piston contains 50 square inches. 

10 " 'V " " 78% " 

12 " " " " 113 " 

14 154 

16 " " " " 201 

lo-inch auxiliary contains 71 square inches. 

12 103 >^ 

16 " " " issy^ " 



ITS USE AND ABUSE 



PERCENTAGE OF BRAKING POWER REQUIRED 



251 



The following table shows the percentage of 
braking power required for engines, tenders, 
passenger and freight cars: 

When plain triples are used the cylinder pres^ 
sure is figured at fifty, but with quick-action 
triples it should be sixty pounds per square inch. 

Engines, 75 per cent of weight on drivers. 

Tenders, 100 per cent of light weight. 

Passenger cars, 90 per cent of light weight. 

Freight cars, 70 per cent of light weight. 

When six-wheel trucks are used on passenger 
cars and have only four pairs of wheels braked, 
the braking power should be figured as go per 
cent of eight-twelfths of the total weight. A 
chair car weighing 90,000 pounds with only four 
pairs of wheels braked should only have a brake 
power of 54,000 pounds. 

TO DESIGN LEVERS FOR A CAR 

When designing the levers for a car you must 
begin by taking the total weight, and where four 
pairs of wheels are to be braked on an eight- 
wheel passenger car, take ninety per cent of the 
weight and divide it by four, which will give you 
the amount of power required for each brake 
beam. To find what the pull should be at the 



252 MODERN AIR-BRAKE PRACTICE 

top of the live lever, measure the height of the 
truck, in order to know how long the live lever 
must be. Having found the length of the lever, 
and knowing what force there must be on the 
brake beam, you proceed as previously ex- 
plained under "Brake Leverage," remembering 
that your live lever is of the second kind, as 
shown in plate 34. 

THE AMERICAN DRIVER BRAKE 

Plate 37 illustrates the American outside 
equalized driver brake, which is now almost uni- 
versally used on engines. 

In order that you may better understand it, I 
will run through the figures for you. There is a 
fourteen-inch cylinder on each side, with a force 
at the piston of 7,650 pounds. The weight on 
drivers is 81,600, and 75 per cent of this is 61,200, 
which divided by 6 means that each wheel must 
have a brake power of 10,200. The length of 
the long arm of the cylinder lever is 24 inches, 
and the short arm is 6. So that 7,650 multiplied 
by 24 equals 183,600, which divided by 6 leaves 
30,600 pounds at the bottom end of the short 
lever. This is carried to the first equalized 
lever, which is 4x8, or a one to two lever, and 
as the applied power is two-thirds the distance 



ITS USE AND ABUSE 



253 




PLATE NO. 37. — THE AMERICAN DRIVER BRAKE 



254 MODERN AIR-BRAKE PRACTICE 

from the fulcrum as the fulcrum is from the 
weight, the short end of the lever has a force of 
two-thirds of the applied power, or 20,400, which 
leaves the other one-third as the weight against 
the first wheel, which is the fulcrum. The 
applied power at the second equalized lever 
being 20,400 pounds, and as the applied power is 
midway between the fulcrum and the weight, it 
is equally divided, which leaves 10,200 at the 
second wheel, and the other 10,200 is carried to 
the third wheel, thus giving each wheel the same 
brake power. 

THE CAM DRIVER BRAKE 

The chief features of the Cam brake requiring 
consideration are the maintenance of such a pis- 
ton-travel that auxiliary reservoir and brake 
cylinder pressures shall equalize at fifty pounds 
when the brakes are fully applied, and of such 
an adjustment of the cams that their point of 
contact shall be in line with the piston-rod; 
otherwise a bending influence will be exerted 
upon the piston-rod. 

To adjust the cams, in order to shorten or 
lengthen the piston-travel or to secure a central 
point of contact, the check nut should be slacked 
off and the screw turned outward to shorten the 
piston-travel, or inward to lengthen it. 



ITS USE AND ABUSE 255 

To calculate the braking power, apply the 
brake and measure the piston-travel; then 
release the brake, insert pieces of one-quarter- 
inch steel wire crosswise between the tire and 
the shoe at the upper and lower ends, and again 
apply the brake; divide the difference of the 
piston-travel by the thickness of the steel, and 
multiply the result by the total force acting 
upon the piston. The result is the pressure of 
one shoe, which, multiplied by four, gives the 
total braking power. Divide this total by the 
total weight upon drivers to obtain the percent- 
age of braking power. 

EXAMPLE 

Weight on drivers, 53,330 pounds. 

Piston-travel, without inserting wires, three 
inches. 

Piston-travel, with one-quarter-inch wires in- 
serted, two inches. 

Total force on piston (eight-inch cylinder 
brake, fully applied), 2,500 pounds. 

I divided % equals 4. 4 multiplied by 2,500 
equals 10,000 pounds. 

10,000 pounds multiplied by 4 equals 40,000 
pounds — the total braking power. 

40,000 divided by 53,330 equals 75 per cent. 



256 MODERN AIR-BRAKE PRACTICE 

THE LOCOMOTIVE TRUCK BRAKE 

Plate 38 illustrates the American Equalized 
Locomotive Truck Brake v^ith Automatic Slack 
Adjuster. Inasmuch as a considerable propor- 
tion of the weight of certain types of locomo- 
tives is carried upon the truck, the importance 
of a well-designed brake upon that part of the 
equipment is self - evident, especially as the 
weight upon this truck frequently equals (and 
often exceeds) the weight of a large capacity 
car. This brake should be maintained in a high 
state of efficiency, which is readily accomplished 
by the aid of the automatic slack adjuster. 

What has been said with reference to the 
maintenance and care of the driver brake 
applies with equal force to the truck brake. 

In concluding this volume the author would 
earnestly impress upon the mind of the reader 
that he should carry the book with him in his 
daily work, as the time is already here when all 
railroad men are expected to have a thorough 
knowledge of the air brake, and unless you are 
already well posted you cannot expect to absorb 
the knowledge if your instruction book is left at 
home. 

You should always keep in mind the fact that 
the human brain is naturally inclined to throw 



ITS USE AND ABUSE 



257 




PLATE NO. 38. — ENGINE TRUCK BRAKE. 



258 MODERN AIR-BRAKE PRACTICE 

off everything that tends to trouble it in any 
way, and as your success as a railroad man will 
depend upon your ability to acquire and retain 
knowledge, I would advise you to remember this 
little motto: 

By reviewing what you think you know, you 
learn to know what you know you know. 



QUESTIONS AND ANSWERS TO 
SECTION III 

THE PHILOSOPHY OF AIR-BRAKE HANDLING, BRAKE 
POWER LEVERAGE, ETC. 

62. What is meant by the philosophy of air- 
brake handHng? 

Ans. — It is a clear and definite understanding 
of the effect produced by different volumes and 
pressures of air in relation to the varying condi- 
tions of track, load, grade and speed. 

63. What is one of the first things an engineer 
should learn in handling trains? 

Ans. — The value of maintaining correct stand- 
ards of pressure in the different parts of the air- 
brake equipment. 

64. What is the percentage of brake power 
allowed on freight cars, passenger coaches, 
engines and tenders? 

Ans. — A tender is braked to 100 per cent of its 
light weight; an engine at 75 per cent of weight 
on drivers; a freight car at 70 per cent of its 
light weight, and a passenger coach at 90 per 
cent of its light weight. When a coach has six- 
wheel trucks and only four wheels braked, the 

259 



26o MODERN AIR-BRAKE PRACTICE 

braking power should be figured as 90 per cent 
of iV of the total weight, 

65. What is the correct piston-travel for loco- 
motives? 

Ans. — As there are two cylinders on a locomo- 
tive both pistons should travel the same, and in 
order to determine what that travel should be, a 
test gauge should be applied and the piston- 
travel set so that the pressure equalizes with a 
full service or emergency application at fifty 
pounds. The smaller brake cylinders usually 
require about three inch piston-travel, and the 
larger cylinders four inches, and as the piston- 
travel on a locomotive is multiplied by two, a 
three-inch travel would mean six inches and the 
four-inch travel eight inches when both sides 
are counted. 

66. What should be the piston-travel on 
cars? 

Ans. — The piston-travel should be eight 
inches running along, and as the equipment 
while running allows a further piston-travel 
than can be obtained while the car is standing, 
the piston-travel should be set at about six 
inches. The rule is, never less than five, nor 
more than seven while the car is standing. 

67. When a car is equipped with a slack 



ITS USE AND ABUSE 261 

adjuster how should the piston-travel be regu- 
lated? 

Ans. — When a car is equipped with new shoes 
the piston-travel should be set at from 6 to 6% 
inches by taking up the slack at the dead levers. 

68. Is there anything that will cause the pis- 
ton-travel to be too short on a car equipped 
with the automatic slack adjuster? 

Ans. — Yes. If some of the slack has been 
taken up on the hand brake, or the position of 
the dead levers has been changed. 

69. When a car is equipped with the slack 
adjuster, what may cause the piston-travel to 
become too long? 

Ans. — Some obstruction may get into pipe B, 
or the pipe may leak, or the slack adjuster cylin- 
der and packing leather may leak. If a car has 
been running with the hand brakes partly set it 
naturally takes up the slack, consequently when 
the brake is entirely released it will take the 
slack adjuster some time to readjust the piston- 
travel, as the cross head is only moved ^V of an 
inch at each operation of the adjuster. 

70. In applying new shoes to a car, what is 
necessary to be done in order to increase the 
shoe clearance? 

Ans. — Turn the ratchet nut to the left and 



262 MODERN AIR-BRAKE PRACTICE 

after the shoes are applied the piston-travel 
may be shortened by turning the adjuster nut to 
the right. 

71. What is the danger of operating trains 
with uneven piston-travel? 

Ans. — Uneven piston-travel causes some of 
the brakes to be released sooner than others, 
and consequently where there is not sufficient 
excess pressure carried to promptly release all 
brakes, it is very liable to either pull the train in 
two or slide the wheels, or cause the wheels to 
become heated from the pressure of the brake 
shoe so that the wheels are broken and the train 
wrecked. 

72. Is there any difference in the way in which 
a passenger or freight train should be stopped? 

Ans. — Yes. All the difference in the world. 
A passenger train should be stopped by making 
two applications and the brake valve thrown to 
release position just before the train comes to a 
dead stop in order to avoid the shock. Whereas, 
in making a freight stop there should be but one 
application and the brakes should not be re- 
leased until the train comes to a dead stop. A 
further difference is, that in making a passenger 
stop where the train is running twenty-five miles 
an hour or over, the initial reduction should not 



ITS USE AND ABUSE 263 

be less than ten pounds, whereas, with a freight 
train the initial reduction should never be over 
seven pounds, excepting with a heavy train on 
descending grades, when a ten-pound applica- 
tion would be right and proper. 

T^' In coupling a locomotive on to a train, 
what should the engineer do? 

Ans. — He should make at least a ten-pound 
reduction and hold his valve on lap until the 
train is fully coupled up in order to prevent the 
tender brake from sticking. 

74. Why are the tender brakes liable to stick 
if the engineer fails to make a reduction when 
coupling on to a train? 

Ans. — F'or the reason that when more trainpipe 
is connected to the tender the air flowing into 
the added trainpipe will cause a reduction at the 
tender triple and set the brake, and as the triple 
piston packing ring on the tender, more than 
any other, is liable to be slightly gummed, it fol- 
lows that in charging up the train while the 
tender brakes are set with a high auxiliary pres- 
sure, the auxiliary and trainpipe pressure on the 
tender is liable to become equalized or nearly so, 
which prevents a sure release of the brake. 

75. In using the high-speed brake, why is it 
that the brakes take hold quicker with the same 



264 MODERN AIR-BRAKE PRACTICE 

amount of reduction than they do when using 
the automatic brake? 

Ans. — It is because the auxiliary is charged to 
no pounds instead of seventy, so that the air 
passes quicker into the brake cylinder. 

76. Would you get a higher brake power with 
a ten or fifteen-pound reduction in using the 
high-speed brake than you would if using the 
automatic brake? 

Ans. — No. Because the same pressure per 
square inch would show in the brake cylinder 
with a ten or fifteen-pound reduction no matter 
which equipment was being used. But should a 
reduction be made with a high-speed brake of 
twenty-two pounds or more, there would be a 
corresponding increase in the brake cylinder 
pressure. 

']'], Why i^ this? 

Ans. — With the automatic brake a reduction 
of twenty pounds will cause the auxiliary and 
brake cylinder pressures to equalize so that a 
further reduction would be simply a waste of 
air; whereas, with the high-speed brake the 
auxiliary and brake cylinder pressures do not 
equalize until a reduction of about twenty-six 
pounds has been made, but when the auxiliary 
and brake cylinder equalizes with the automatic 



ITS USE AND ABUSE 265 

brake equipment in service application, there is 
only a pressure of fifty pounds in the cylinder if 
the piston-travel is correct; whereas, with the 
high-speed brake equipment the auxiliary and 
brake cylinder will equalize with a service appli- 
cation at about sixty-eight pounds, and in an 
emergency application at about eighty-eight 
pounds where iio-pound trainpipe pressure is 
used. 

78. In making a two-application stop with a 
passenger train, how should the brakes be 
released after the first application and why? 

Ans. — In making a two-application stop the 
initial reduction should be from ten to twelve 
pounds according to the speed of the train, and 
as soon as the momentum of the train has been 
checked, one or two more reductions should be 
made until the auxiliary and brake cylinder 
pressures have equalized, when the brake valve 
handle should then be thrown to full release 
position just long enough to insure that all 
brakes are released, when the handle should be 
brought to lap position, until it is time to make 
the second application. The reason for this is 
because the auxiliaries cannot be recharged 
between the first and second application, and by 
holding the valve on lap it allows the trainpipe 



266 MODERN AIR-BRAKE PRACTICE 

and auxiliary pressures to equalize so that on 
the first reduction, when the second application 
is begun, the triples will move promptly and 
pass the air from the auxiliary into the brake 
cylinder. 

79. In handling a freight train, why should the 
engineer always listen to the trainpipe exhaust 
in making a service application? 

Ans. — Because by the length of the blow at 
the trainpipe exhaust he can tell whether he has 
a long or short trainpipe. 

80. In case of a break-in-two, what should the 
engineer always do? 

Ans. — Promptly close the throttle and lap the 
brake valve, in order to stop as quickly as pos- 
sible so that the rear end of the train will not 
hit the forward end so hard when they come 
together, and the lapping of the valve saves the 
main reservoir pressure. 

81. How should sand be used on a rail? 
Ans. — Sand should always be used before the 

speed of the train has been materially reduced, 
as otherwise it is almost sure to spot the 
wheels. 

82. Why should the throttle never be opened 
immediately after releasing the brakes on a 
freight train? 



ITS USE AND ABUSE 267 

Ans. — Because the slack must be allowed to 
adjust itself first in order to prevent pulling the 
train in two. 

83. What is a common cause for stalling trains 
on heavy grades? 

Ans. — The continual throwing of the brake 
valve handle to full release and back to running 
position. By doing this the engineer gets the 
trainpipe charged higher than what the feed 
valve is set for and when the trainpipe pressure 
has been raised above seventy pounds, if the 
handle is placed in running position, no air can 
pass through the feed valve attachment until 
the trainpipe leaks have reduced the pressure 
below what the feed valve is set at, and as a 
consequence the brakes get to dragging and 
thereby stall the train. 

84. What is the danger of bleeding off a stuck 
brake and allowing it to run without cutting it 
out? 

Ans. — A brake that is inclined to stick and has 
to be bled off is almost sure to stick again at a 
time when the trainmen cannot get to it to bleed 
it unless there is a release signal on the car, and 
as a consequence the wheels are liable to 
become heated and either slide them or break 
them and ditch the train. 



268 MODERN AIR-BRAKE PRACTICE 

85. What number of cars In a train should be 
air braked ? 

Ans. — All of them, if possible, but a recent law 
passed by the National Congress requires that 
fifty per cent of all cars in a train shall be 
equipped with air brakes in good condition. 




?N\c>N ?v'^erik'?v V. \ 



Q>\iK.^\i'a"^'p> 




Sic*" 

am 



/ 



Tx-b>^'^\S'^'^ 'iT^k?^^ 



rr i ~rr ,t r it^ 



PfnuM/^/AfiY ftesenvom. 



PLATE 43 

Axle Driven Compressor Straigfht Air Brake 
Equipment for Electric Traction Cars 




COl//^i.//^G 



TffA/L£n c/in 



CHAPTER V 

THE STRAIGHT AIR BRAKE AS USED ON ELECTRIC 
TRACTION CARS* 

Motormen and conductors of electric cars 
should possess something more than a mere 
knowledge of how to apply and release brakes. 
They should understand the mechanical prin- 
ciples represented in the brake, and should know 
how to detect, remedy and report any and all 
kinds of defects which may arise in the straight 
air-brake equipment. 

The changed conditions of the past few years 
have materially raised the personnel of electric 
railway employes. There was a time when 
almost any kind of a man could find employment 
on street railways, but to-day a man must pos- 
sess a certain amount of ability before even his 
application will be considered. These changed 
conditions are mainly due to the advent of inter- 
urban railway traffic. 

The cars operated in interurban service are 
not only very heavy, but the speed at which 

*A special index for this chapter has been prepared and 
immediately follows the index of the Automatic Equipment. 

269 



270 MODERN AIR-BRAKE PRACTICE 

they travel is in many cases faster than ordinary 
steam railroad cars. Many steam railroads feel 
that they are doing very well if their freight 
schedules average twenty-five miles an hour, 
whereas nearly all interurban electric railways 
make an average schedule of at least thirty miles 
an hour. Such being the case, it is highly im- 
portant that motormen and conductors master 
as fully as possible all detailed knowledge of the 
operation and maintenance of the brake appa- 
ratus. 

The question of brake power on electric rail- 
ways is quite a different proposition from that of 
steam railways, for the reason that with steam 
railroads there is but one kind of power brake 
in general use, which is the automatic air brake, 
whereas with the electric railways there are 
many kinds of power brakes in use. For 
instance, there is what is known as the hydraulic 
brake; and the magnetic brake; and of air brakes 
there are two systems in use, one is known as 
the automatic and the other the straight air 
brake. 

Each kind of brake, of course, has its special 
advantages, but when all things are taken into 
account there is no brake so good and reliable 
for electric railways as an air brake, and as the 



ITS USE AND ABUSE 



271 



majority of electric roads operate their cars 
singly, it naturally follows that the straight air 
brake is the best all-around brake that can be 
used. 

While there are different systems of straight 
air brakes in use, some of which use what is 
known as the motor compressor, there is, how- 
ever, a system now being universally installed, 
which is undoubtedly destined to supersede all 
others and is known as the Standard Traction 
Brake Company s Axle Compressor System, manu- 
factured by the Westinghouse Air-Brake Com- 
pany. 

As the Westinghouse Air-Brake Company 
were the first to invent and operate the straight 
air brake, it naturally follows that they are in 
better position to bring the brake to a state of 
perfection than almost any one else, as in their 
immense plants in Wilmerding, Pa., they have 
every means at their command for doing so. 

A student of straight air brakes as used on 
electric railways, should carefully read Section 
III of this book, as it will give him a general 
idea of brake handling and enable him to more 
readily grasp the points in which he is directly 
interested. 

In order to understand the action of the 



272 MODERN AIR-BRAKE PRACTICE 

straight air brake, it is necessary to begin by 
studying the brake levers and cyhnder under 
the body of the car. 

By referring to Plate 39 you will see how the 
cylinder and levers are connected up. This 
diagram shows you how either the hand-brake 
staff or the air cylinder may be used to apply 
the brake. Where the hand-brake staff is used 
the levers are pulled forward, whereas when the 
brake is set by air the levers are pushed forward 
by the piston in the brake cylinder. 

As the purpose of this book is to treat of com- 
pressed air only, I will describe the geared 
axle-driven compressor instead of the motor 
compressor, for the reason that with the axle- 
driven compressor no electricity is required to 
operate the compressor, or control the governor. 

The parts necessary to complete the straight 
air-brake equipment on electric traction cars is 
as follows: 

An air compressor, which is geared to and 
driven by the car axle, for the purpose of com- 
pressing the air used in the brake equipment. 

An automatic regulator or governor, for the 
purpose of controlling the working of the com- 
pressor and regulating the amount of air to be 
compressed. 



274 MODERN AIR-BRAKE PRACTICE 

A reservoir, in which the air compressed by 
the pump is stored ready for the instantaneous 
application of the brakes. 

A brake cylinder, into which the compressed 
air is allowed to flow whenever it is desired to 
apply the brakes, connected to which is a system 
of levers, rods and brake shoes, as shown on 
Plate 39. 

An operating valve mounted at each end of 
the car for the purpose of controlling the flow of 
the compressed air into or out of the brake 
cylinder, as desired. 

The system of piping with various cut-out 
cocks, etc., connects the above-mentioned parts 
together. 

THE GEARED AXLE-DRIVEN COMPRESSOR 

As the first thing necessary to a power brake 
is the generating of power, we will begin by con- 
sidering the air compressor. 

Plate 40 is what is known as a "ghost" cut, the 
white lines representing the parts through which 
you are looking, in order to get an internal view 
of the compressor. The compressor is double 
acting, and has horizontal axis of cylinder at 
right angles to the car axle; in other words, the 
car axle operates through the bearing, which, in 



ITS USE AND ABUSE 



275 



cut 40, is shown to be empty. There are two 
discharge valves on the compressor and they are 
located on top of the cylinder, one at either end, 
and the discharge port is located midway 
between the discharge valves, as shown in Plate 
40. Now, if you will look lower down, you will 
notice that by the side of the cylinder there are 
two other valves, one of which is shown in 
"ghost" outline; these two valves are known as 
suction valves, or, as we say in the automatic 
equipment, receiving valves. Leading from 




PLATE NO. 40— AXLE-DRIVEN AIR COMPRESSOR 

each of these valves are cylindrical chambers 
connected to each other by a passage that 
arches over the crank-shaft end-bearing, and 



276 MODERN AIR-BRAKE PRACTICE 

between the two receiving valves is the receiving 
port, through which the atmospheric air is taken 
into the compressor. 

These four valves, together with their renew- 
able seats, are interchangeable, and have no 
springs to wear out, or gum up. 

The cylindrical chambers beneath the receiv- 
ing valves are connected by means of a fitting, 
either end of which is piped to the automatic 
regulator, or governor. 

The compressor piston is made of a single 
casting in the form of two disks connected at 
the top and bottom. Each disk is provided with 
a spring packing ring, and carries on its inner 
side a rectangular surface parallel to the ends 
of the piston, thus combining a piston and slotted 
cross-head in one piece. The axis of the crank 
shaft, which runs parallel with the axle of the 
car, intersects the axis of the cylinder at its mid- 
dle point; thus the crank shaft passes between 
the disks of the piston and imparts to them a 
reciprocating motion by means of the crank- 
brass slide between the parallel faces on the 
interior of the piston disks. 

As the compressor operates very rapidly at 
times, it is necessary that all of these parts run 
in a bath of oil. On the other side of the cylin- 



ITS USE AND ABUSE 277 

der there is a flange by which it is bolted to the 
oil-tight housing that encloses the gear on the 
crank shaft, as well as the driving gear secured 
to the axle of the car. This housing is provided 
with bearings on the axle, which serve to keep 
the two gears meshed together; one end of the 
compressor is supported by these bearings and 
the other end is supported by brackets mounted 
upon it and the truck frame, respectively, with a 
rubber cushion between them to deaden the 
vibration. This type of compressor is especially 
adapted for mounting on the same axle with the 
car motor, as the axle gear and its bearings take 
up only a small space on the axle, and the bal- 
ance of the housing and the pump cylinder 
occupy the space back of the motor. There are 
no stuffing boxes whatever in the entire equip- 
ment, and all parts that need lubrication are 
provided with oil wells and grease pockets. 
The manufacturers of the geared axle-driven 
compressor make seven different styles, in order 
to meet the varying conditions of the different 
kinds of service. But in all cases the diameter 
of the axle and pump gear is so proportioned 
that the piston speed never exceeds the safety 
limit. All of the compressors are made with a 
capacity double that required for a motor car 



278 MODERN AIR-BRAKE PRACTICE 

with one trailer, running under the most severe 
conditions of service for which it is designed, so 
that a large proportion of the time the compres- 
sor is running with the pump automatically cut 
out of operation. 

The automatic regulator or governor consists 
of a chamber which is always in direct communi- 
cation with the reservoir, one wall of which is 
formed either by a diaphragm or piston, on one 
side of which is the reservoir pressure and on 
the other atmospheric pressure and a graduated 
spring. As the pressure in the reservor increases, 
the piston or diaphragm moves outwardly, which 
causes a D slide valve in the regulator chamber 
to move outwardly and uncover a port in the 
slide-valve seat, which admits compressed air to 
closed chambers, and when the pressure is 
changed the slide valve moves inwardly and 
connects this port to one leading to the atmos- 
phere. The closed chambers just referred to 
are located in the body of the pump cylinder, 
directly beneath the receiving valves, and are 
connected by hose to the regulator. Each of 
the two chambers is provided with an air-tight 
piston, so that when the reservoir pressure 
reaches the desired amount the compressed air 
is admitted beneath them, thereby causing the 



ITS USE AND ABUSE 279 

receiving valves to be lifted, so that they are cut 
out of operation and the pump is thereby thrown 
out of action. When the reservoir pressure 
has fallen below the standard at which the gov- 
ernor is set, the D slide valve is forced to its 
inward position by the spring, thereby allowing 
the air to escape from trip-piston chambers, and 
as the pistons are forced down by springs pro- 
vided for the purpose, the receiving valves seat 
themselves, and the pump is again in operation 
until it is cut out again by the regulator. This 
style of regulator is undoubtedly the best that 
can be devised, for the reason that regulators 
which allow the pressure to be discharged into 
the atmosphere when the pump is cut out usually 
leak very badly, and have the further disad- 
vantage of keeping the pump valves in service 
all the time. 

THE OPERATING VALVE 

For the purpose of controlling the flow of the 
air either into or out of the brake cylinder, there 
are ordinarily two operating valves on each car, 
one at each end, and they are made in two 
forms. Form OVT, shown in Plate 41, has the 
valve proper placed upon the platform with the 
operating head directly above it at the level of 



28o MODERN AIR-BRAKE PRACTICE 



the motorman's hand. On the top of this head 
is a double gauge, the red hand of which shows 
the reservoir pressure and the black hand the 
pressure in the brake cylinder. Owing to this 
convenient location the motorman 
cannot fail to know at all times the 
pressure in his reservoir and just 
how much brake power he is 
using. The gauge is protected by 
heavy plate glass and is in practi- 
cally no danger of being broken. In 
the head, directly below the gauge, 
is a revolvable casting provided 
with a horizontal, cylindrical socket 
and a latch, so that when the 
handle is inserted in the socket it 
lifts the latch and the handle may 
be rotated, but when the handle 
is withdrawn the casting is auto- 
matically locked in Its place. The 
shell of the head is made so that 
the handle can be inserted or 
removed only when it is in one par- 
ticular position, usually that of lap position, when 
all ports in the valve are closed. This prevents 
any one tampering with the valve at the rear end 
of the car. The revolvable casting in the head is 




PLATE NO. 41 — 

OPERATING VALVE 

O V T 



ITS USE AND ABUSE 281 

connected to the stem of the valve proper by- 
means of a vertical shaft enclosed in a pipe shield 
and provided with a flexible coupling. 1 his stem 
is provided with a pinion, which engages with a 




PLATE NO. 42 — OPERATING VALVE O V G 

rack mounted on the slide valve, so that when 
the handle is moved the valve slides from side 
to side between its guides. 
When it is inconvenient to place the valve on 



282 MODERN AIR-BRAKE PRACTICE 

the floor, type OVG operating valve, as shown 
in Plate 42, is used; with this valve the head is 
mounted upon and forms a part of the valve 
casing, but in all other respects it is identical 
with valve OVT. 

Just below the slot in which the handle of 
these valves move is a little shelf, on which is 
clearly marked the different positions to which 
the brake-valve handle may be moved. There 
are four positions of the operating valve handle, 
viz., release, lap, service, and emergency. Re- 
lease position is marked "off," meaning that the 
brakes are off or released. Lap position means 
that the brake cylinder is cut off from communi- 
cation with both the atmosphere and the reser- 
voir. Service position means that the valve is 
in position so that a small port is open for the 
purpose of allowing the reservoir pressure to be 
gradually admitted to the brake cylinder for 
making a service stop. Emergency position is 
used when the full brake power is required and 
when the handle is in this position the largest 
port in the brake valve is open, permitting the 
brakes to be applied instantly. 

A very little practice will enable a motorman 
to handle his brake in such a manner as to avoid 
the shocking of passengers and the sliding of car 



ITS USE AND ABUSE 283 

wheels. Emergency position should never be 
used except in case of supposed or actual danger. 
But whenever it is required to use the emergency 
the handle of the operating valve should be 
immediately thrown to that position and held 
there until the car stops or the danger is past. 

Plate 43 illustrates the arrangement of the 
straight air-brake equipment on a motor car 
with trailer car attached. As each part is plainly 
marked on the illustration, no further explana- 
tion is necessary to describe the plate. 

It will be noticed that in this illustration there 
are two reservoirs; one is known as the pre- 
liminary reservoir and the other as the main 
reservoir. This system of having two reservoirs 
applies only where the geared axle-driven com- 
pressor is used, as when the motor-driven com- 
pressor is used only one reservoir is required. 

With the equipment illustrated on Plate 43 the 
passage of the compressed air is as follows: 
from axle-driven compressor through the check 
valve to the preliminary reservoir, from the pre- 
liminary reservoir through trainpipe to the oper- 
ating valves on either end of the car. And when 
the handle of the brake valve is moved to serv- 
ice or emergency position the air. passes through 
the brake valve into the brake-cylinder pipe and 



284 MODERN AIR-BRAKE PRACTICE 

from thence into the brake cylinder. When the 
air leaves the preliminary reservoir and while it 
is filling the trainpipe it is also passing to the 
automatic regulator or governor. 

You will notice a duplex check valve on the 
end of the main reservoir. This is placed there 
for the purpose of allowing thirty-five pounds of 
air to be accumulated quickly in the preliminary 
reservoir in order to make a stop within a very 
short distance after the car first starts out. 
When the pressure rises to thirty-five pounds 
the duplex check valve is opened and the main 
reservoir is then filled along with the rest of the 
equipment up to the standard pressure at which 
the automatic regulator is set, which is 45 pounds. 

In releasing the brake, the handle of the oper- 
ating valve is thrown to the position marked 
"off," which allows the air in the brake cylinder 
to flow back through the brake valve and out to 
the atmosphere through the muffler beneath the 
car platform. 

Again referring to Plate 39, 1 wish to call your 
attention to the small equalizing lever, marked 
GA. This is a patented modification of the 
well-known steam railroad leverage, which is 
especially adapted to the requirements of trac- 
tion service. By this system of leverage greater 



ITS USE AND ABUSE 285 

brake power Is obtained by the hand brake with- 
out the use of an excessively long cross lever. In 
the ordinary construction the point of attach- 
ment of the chain to the cross lever is located in 
line with the axis of the brake cylinder, and the 
pull is therefore directly at the end of the lever 
B, and to obtain proper hand-brake power on 
heavy cars the lever marked X, in Plate 39, 
would have to be longer than the width of the 
car. As this would be impracticable, instead of 
having a long lever X in order to get the proper 
hand-brake power, the lever A is introduced, 
thereby overcoming the trouble completely, 
besides giving a much better clearance between 
the pull rods and the wheels. 



QUESTIONS AND ANSWERS TO 
CHAPTER V 

COVERING THE OPERATING AND MAINTENANCE O- 

THE STRAIGHT AIR-BRAKE EQUIPMENT 

ON ELECTRIC TRACTION CARS 

1. What is the principal difference between 
the automatic air brake and the straight air 
brake? 

Ans. — The automatic air brake requires the 
action of a triple valve in order to charge, set 
and release brakes, whereas with the straight 
air brake the operating of the brake valve regu- 
lates the flow of the air into and out of the brake 
cylinder. 

2. As compressed air is the power by which 
the brakes are applied, what is it that compresses 
the air? 

Ans. — A geared axle-driven air compressor. 

3. Can you explain the operation of the axle- 
driven compressor? 

Ans. — There is a gear attached to the axle of 
the car, which is meshed into a gearing to which 
is connected a crank shaft, which passes through 

the middle of the pump cylinder, in which are 

286 



ITS USE AND ABUSE 287 

two pistons which are connected to the crank 
shaft in such a manner that as the shaft revolves 
it gives to the pistons a reciprocating movement, 
and as there are two receiving valves which per- 
mit the atmospheric pressure to enter the pump 
cylinder the motion of the pistons compresses 
the atmospheric air and forces it through two 
discharge valves into suitable reservoirs, in 
which the air is stored ready for use in applying 
the brakes. 

4. What controls the action of the air com- 
pressor? 

Ans. — An automatic regulator, or governor. 

5. At what pressure should the regulator cut 
out the pump? 

Ans. — At forty-five pounds. 

6. How does the regulator control the action 
of the pump? 

Ans. — When forty-five pounds has been accu- 
mulated in the reservoir the piston in the regu- 
lator is forced outwardly by the reservoir 
presure. As there is a D slide valve attached 
to this piston, it is moved so that the port in the 
valve seat is uncovered, which admits com- 
pressed air to the under side of the trip pistons 
below the receiving valves, causing them to 
unseat the receiving valves so that the pump 



288 MODERN AIR-BRAKE PRACTICE 

cannot compress any more air. When the reser- 
voir pressure falls slightly below forty-five 
pounds the graduating spring in the regulator 
forces the piston and slide valve inward, so that 
the air contained in the chamber below the trip 
pistons can escape to the atmosphere, and the 
pressure having thus left the under side of the 
trip pistons the spring on the opposite side forces 
the trip pistons down and allows the receiving 
valves to again seat themselves and thereby put 
the pump again into action. 

7. At what pressure is the duplex check valve 
set between the preliminary and main reser- 
voirs? 

Ans. — At thirty-five pounds. 

8. Why is it set at thirty-five pounds? 

Ans. — In order that sufficient brake power 
may be accumulated in as short a run as only 
one hundred yards, and also to enable sufficient 
brake pressure to be maintained on the inter- 
urban cars when running at slow speed through 
cities. 

9. What amount of pressure should there be 
in the brake cylinder in making a service 
stop? 

Ans. — In making a service stop the brake cyl- 
inder should maintain from twenty-five to thirty 



ITS USE AND ABUSE 289 

pounds, as indicated by the black hand of the 
gauge. 

10. What pressure should there be in the 
brake cylinder in making an emergency action? 

Ans. — Forty pounds, which is also indicated 
by the black hand of the gauge. 

11. In what position should the handle of the 
brake valve be carried in running along? 

Ans. — If the brake valve is tight the handle 
should be carried on lap position, but if the 
valve leaks slightly the handle should be carried 
in release or at the position marked "off." 

12. If the valve leaks slightly and the handle 
was carried on lap, what effect would it have? 

Ans. — It would cause the brakes to gradually 
creep on. 

13. What attention should be paid to the 
lubricant in the housing of the axle-driven com- 
pressor? 

Ans. — The oil should never be allowed to get 
below the pump shaft. 

14. How often should the oil be replenished? 
Ans. — This depends upon the service that the 

car is in and the condition of the bearings on the 
axle, so that it is not possible to say just how 
often it will be necessary to replenish the oil. 
But when a car is first put into service, the cover 



290 MODERN AIR-BRAKE PRACTICE 

should be removed from the gear housing at 
least once a week and enough grease be added 
to bring the level well above the pump shaft. 
By noting the amount found remaining in the 
housing each time, it can be readily seen if it 
needs grease oftener or if it will run for a longer 
period without replenishing. 

15. What kind of a lubricant should be used? 

Ans. — A grease about the consistency of vase- 
line. A very heavy West Virginia crude oil is 
the best for the cylinder, and it should be kept 
at the level of the crank shaft. It should be 
poured in through the opening on the top of the 
cylinder, or extension of the housing. It is very 
Important that the lubrication be carefully 
looked after. 

16. What other points should be looked after 
in maintaining the straight air-brake equip- 
ment? 

Ans. — Other than attending to the proper 
supplying of lubricant there is little to do besides 
keeping the brake shoe-slack taken up and see- 
ing that no nuts have. become loosened; this lat- 
ter inspection should be made at least once a 
day, if possible, and need take but a minute, as 
all nuts and bolts that can loosen are on the out- 
side. 



ITS USE AND ABUSE 291 

17. How often should the compressor be taken 
off the axle and cleaned and examined thor- 
oughly? 

Ans. — This should be done at regular intervals 
of three months, if the car is in hard service. 
The bearings on the axle should then be re- 
placed and the old ones re-babbitted for the next 
one. As this is practically the only place where 
oil can escape from the compressor it is neces- 
sary to keep these bearings close to the axle. 

18. If the pressure cannot be raised in the 
reservoir, what-should you do? 

Ans. — Disconnect the discharge hose union, 
and while the car is running hold the hand over 
the opening, and if for each revolution of the 
axle there are two equally sharp spurts of air, 
the pump is all right, but should you not feel 
these sharp spurts of air, the discharge and 
receiving valves should be examined, as they 
may be stuck. A large leak is somewhat diffi- 
cult to locate, as with the axle compressor the 
car must be in motion to do any pumping. For 
this reason roads having a large number of air- 
brake equipments should have a stationary com- 
pressor, either belt or motor driven, which with 
two reservoirs make a very convenient testing 
outfit. If the discharge and receiving valves are 



292 MODERN AIR-BRAKE PRACTICE 

found to be all right, the lack of pressure may 
be caused by the air escaping through the oper- 
ating valve, as dirt may have gotten between the 
valves on its seat. If this is found to be all 
right, the pipes should be examined to see if 
they have cracked anywhere, or if a fitting has 
broken. 

ig. If the compressor fails to pump, what 
should be done? 

Ans. — Remove the fitting under the suction 
valves and see if the little trip pistons are free; 
if the suction or regulating pipes were not prop- 
erly cleaned, dirt may cause one of the pistons 
to stick and hold the suction valve open. It is 
also possible to feel from below whether the 
valves are seating properly. 

20. If one suction valve sticks and the other 
one does not, what is the effect on the pump? 

Ans. — The pump will attain maximum pres- 
sure, but it will take twice as long to do it. 

21. If one discharge valve sticks open, what 
effect will it have? 

Ans.— The pump will only raise the pressure 
to about twenty pounds. 

22. As the pump valves are all interchange- 
able, what precaution should be taken after 
cleaning^ them? 



ITS USE AND ABUSE 293 

Ans. — You must be sure to put them back in 
their old seats. Otherwise they are liable to 
leak, as no ground valves are interchangeable 
without re-grinding on the new seats. 

23. Should the pump fail to cut out at the 
point at which the regulator is set, what should 
you do? 

Ans. — Take down the trip fitting and see that 
the trip pistons are free; instances have occurred 
of a long trip-piston packing leather being caught 
between the trip fitting and cylinder body when 
bolting the fitting on. 

24. When the compressor valves are all in 
good order and the operating valve is tight, 
what might cause the compressor to pump 
slowly? 

Ans. — A kink in the suction hose by which it 
is doubled over on itself will cause the compres- 
sor to pump slowly, owing to the diminished sup- 
ply passage. 

25. In removing the cover of the housing to 
oil the compressor, what should you be partic- 
ular to notice? 

Ans. — That nothing is allowed to drop into 
the housing; the lodging of a stray bolt or nut 
between the gears will destroy the whole ma 
chine. 



INDEX 



INDEX TO AUTOMATIC AND HIGH-SPEED BRAKE EQUIPMENT 

[For Index to Straight Air-Brake Equipment see Special Index 
which follows this one.] 



Action, of equalizing discharge 
valve in brake valve, 130. 
of air end of pump, 101. 
Air, course through brake valve, 
136. 
course through triple, 34. 
end of pump, action of, 101. 
Air brake, why so badly neg- 
lected, 10. 
equipment, testing and in- 
spection of, 220. 
equipment, parts described, 

19. 
handling, philosophy of, 220. 
law, passage of, 15. 
release-signal, 21. 
Air sander, 187. 
Air valves, lift of in pump, 

112. 
American driver brake, 252 and 

253. 
Angle-cock, effect on brakes if 

closed, 10. 
Applying brakes, kinds of ap- 
plication used in, 40. 
Application of brakes, how 
made, 192. 
meaning of, 224, 



Applications of brakes, different 

kinds of, 40. 
Association, law of, 8. 
Automatic reducing valve, high- 
speed brake, 145. 
slack adjuster, 77. 
Auxiliary, recharging, 34. 
release valve, 69. 
release valve leaking, 72. 



Bad brakes and bad handling, 

cost of, 14. 
Bell ringer, 187. 
Bleeding off, brakes with plain 
triple, 67. 
stuck brakes, danger of, 267. 
Blow at trainpipe exhaust, 208. 
triple exhaust, cause of, 218. 
Braking power, percentage re- 
quired, 251. 
Brake cylinder leakage groove, 
69. 
cylinders, sizes of, 220. 
high-speed, described, 141. 
leverage, 239. 
levers illustrated, 244. 
setting on head end first, 
cause of. 46. 



295 



296 



INDEX 



Brakes, sticking, cost of, 72. 

how to release from top of 
car, 177. 
Brakevalve, defects, 207. 

D-8, engineer's, 117. 

different styles of, 120. 

r-6, illustrated, 128. 

G-6, described, 137. 



Calculating brake power, rule 

for, 245. 
Cam driver brake, 254. 
Car levers, how to design, 251. 
Cavity D described, 133. 
Chamber Y, 59. 
Changing quick-action equip- 
ment into high-speed, 175. 
Charging auxiliary, 34. 
Check valve, for straight air 

equipment, 157. 
of triple valve, necessity for, 

58. 
Cleaning pump, 214. 
Combined straight air and 

automatic engine brake, 

156. 
Conductor's valve, function of, 

94. 
Course of air, through engineer's 

brake valve, 136. 
through quick-action triple, 

51. 
through triple, 34. 
Cylinder pistons and auxiliaries, 

diameters of, 250. 
Cylinders, sizes of, 220. 

D 
D, cavity, 133. 
D-8 engineer's brakevalve, 117. 



Defects, in brake valve, 207. 
in gauge, 206. 
in pump, 203. 
of pump governor, 206. 
in whistle signal system, 209. 
Defective triple, how to locate, 

178. 
Designing, car levers, 251. 

levers, 243. 
Diameters of cylinder pistons 

and auxiliaries, 250. 
Discharge valves, in pump, ac- 
tion of, 102. 
leaky, test for, 204. 
Driver brake, described and 

illustrated 233 and 252. 
Driver brakes, keeping set with 

train brakes released, 67. 
Double check valve, straight 

air equipment, 157. 
Duplex pump governor, de- 
scribed, 144. 

E 

Emergency application, action 
of triple in making, 62. 

position on brake valve, 
described, 130. 
Emergency position quick-ac- 
tion triple valve, illus- 
trated, 60. 

valve, 63. 
Engineer's brake valve, G-6, 
illustrated, 138. 

G-6 described, 137. 

defects, 207. 

D-8, 117. 

F-6, illustrated, 128. 

positions on, 126. 

parts of F-6 style 131. 

for straight air, 162. 



INDEX 



297 



Engineer's brake valves, differ- 
ent styles of, 120. 
Enginemen, what they should 

know, 23. 
Equalizing discharge valve, 
function of 188. 
discharge valve in brake 

valve, action of, 130. 
reservoir broken off, effect 
of, 216. 
Equalization of pressure, rules 
for, 220. 
anecdote relating to, 16. 
lack of knowledge of, 14. 
in auxiliary and brake cylin- 
der explained, 154. 
in running position, 207. 
Equipment described, 19. 
Excess pressure, meaning of 
195. 



F-6 brake valve, described, 12. 
Feed groove in triple, 35. 
Feed valve, attachment, de- 
fects of, 208. 
attachment, function of, 

189. 
new slidevalve, 139. 
old style, described, 134. 
Failure, to charge auxiliary, 
cause of, 199. 
to maintain equipment, dan- 
ger of, 198. 
of pump governor to shut 

off pump, cause of, 217. 
to release by bleeding, cost 

of, 45. 
to release brakes, cause of, 

233. 
to set brakes, cause of, I'^O. 



Failure of trainpipe exhaust to 
open, cause of, 209. 
of whistle to respond, cause 
of, 217. 

G 
Gauge, black hand showing 
more pressure than red 
hand, cause of, 217 
defects, 206. 
how connected, 137. 
Governor, pump, described, 112 
Graduating stem, function of, 
44. 
spring, function of, 44. 
valve, function of, 40. 

H 

Handling trains, 224. 

with high-speed brakes, 227. 
Heavy grades, train handling 

on, 234 
High-pressure control, 150. 
High-speed brake, illustrated, 
143 and 146. 
reducing valve, 145. 
train handling, 227. 
How to detect and remedy 

defects, 212. 
Hostlers, advice to, 236. 

I 
Improper use of retaining valve, 
danger of, 17. 



Jiggling of pump, 205. 

K 
"Kicker" or defective triple, 
cause of, 218. 
how to find, 178. 
Kinds of levers, 240. 



298 



INDEX 



Lap position, on engineer's 
brake valve, described, 
127. 
of triple valve, 41. 

Law governing air-brake equip- 
ment, national, 15. 

Leaking auxiliary release valve, 
72. 

Leaky, discharge valve, how to 
test for, 204 and 213. 
rotary, testing for, 215. 
packing rings in air end of 

pump, effect of, 212. 
packing rings in pump, test 
for, 205. 

Leakage groove in brake cyl- 
inder, 69. 

Leaks in main reservoir, train- 
pipe or auxiliary, effect of, 
37. 

Length of trainpipe, how to 
determine, 229. 

Leverage, 239. 
rules for, 220. 

Levers, how to design, 243. 

Lift of air valves in pump, 
112. 

Little drum or equalizing reser- 
voir disconnected, effect 
of, 216. 

Locomotive truck brake, 256. 

Logic, law of, 8. 

Losing equalizing reservoir, ef- 
feet of. 216. 

M 

Making running tests, 231. 
Main reservoir pressure equal 

to boiler pressure, one 

cause of, 121. 



N 

Number of cars required to be 

air braked by law, 267. 



Oil, kind of, to be used in pump, 
214. 
use of in pump, 111. 
Oiling air end of pump, re- 
quirements, 214. 
pump, 110. 
Old style feed valve described, 

134. 
Over-confidence, danger of, 12. 



Packing rings in pump, leaky 

test for, 205. 
Packing ring of triple piston, 38. 
Parts constituting equipment, 

19. 
Parts of F-6 brake valve 131. 
quick-action triple valve, 

50. 
Partial service application, 43. 
Passenger trains how to handle, 

224 and 229. 
Percentage of brake power 

required, 251. 
Philosophy of air-brake hand- 
ling, 220. 
Pipe, names of, 186. 
Piston-travel. 223. 

uneven, danger of, 15. 
rules for, 260 
Plain triple valve, 27. 
illustrated, 30. 
old style, illustrated, 64. 
Pounding of pump, 205. 
Pressure, excess, meaning of, 

195. 



INDEX 



299 



Pressure, increased in making 
emergency, cause of. 63. 

trainpipe, standard, 195. 
Pressure-retaining valve, 73. 
Pressures carried with quick- 
action and high-speed 
equipment, 195. 

carried with high-pressure 
control, 195. 

equalize in running position, 
207. 
Principle of the triple valve, 26. 
Pump, difference between 8-in. 
and 9Hn-, 180. 

discharge valves, action of, 
102. 

8-in. explained, 96. 

9Hn., 103. 

9i-in., illustrated, 105. 

governor, illustrated, 112. 

governor defects, 206. 

governor, duplex, 144. 

how to start, 101. 

jiggling, cause of, 213. 

jiggling or dancing, 205. 

oiling, 110. 

pounding, cause of, 205-214, 

running hot, 204. 

receiving valves, action of, 
102. 
Pumps, right and left hand, 109. 

Q 

Questions and answers to Sec- 
tion 1 — parts and their 
duties, 173. 

to section 2, cause of air- 
brake defects, and how to 
detect and remedy, 212. 

to section 3, philosophy of 
air-brake handling, 259. 



Quick-action or defective triple, 
cause of, 202. 
triple, emergency position, 
illustrated, 60. 

R 
Receiving valves in pump, 

action of, 102. 
Recharging auxiliary reservoir, 

235. 
Reducing valve, high-speed 

brake, set at, 175. 
Releasing brakes, explained, 
193. 
method of, 231. 
in running position, danger 
of, 193. 
Release brake, how triple acts 

to, 32. 
Release-signal, 21. 
explained, 85. 
illustrated, 86 and 88. 
location on cars of the, 176. 
valve, 73. 
Release valve on auxiliary, 69. 
Reservoirs, sizes of, 220. 
Retaining valve, 73. 
Rotary valve, function of, 188. 
Reversing engine, 230. 
plate in pump, 182. 
valve of pump, 180. 
Right and left hand pumps, 109. 
Rules, for calculating brake 
power, 245. 
and tables for computing 
brake power, 220. 
Running position on engineer's 
brake valve, described, 127, 
S 
Safety valve for high-speed 
brake, 179. 



300 



INDEX 



Sand, how to use, 230. 
Setting out cars, 234. 
Service application, partial, 43, 
position, engineer's brake 
valve, 127. 
Signal, release, 21. 
Sizes of cylinders and reservoirs, 

220. 
Slack adjuster, automatic, 77. 
defects, cause of, 261. 
illustrated, 78 and 80. 
Slidevalve feedvalve described, 

139. 
Slide valve of triple, 28. 
Starting pump, method of, 101. 
Steam end of 9|-in. pump, 184. 
Sticking triple, how to detect, 

219. 
Stopping distance required, 221. 
Straight air-brake equipment 
for engines, 156. 
for electric cars, see special 
index. 
Straight air-brake valve 162. 

illustrated, 164 and 165. 
Stuck brakes, cost of, 72. 



Taking water, 233. 

Tender brake sticking, cause of, 

232. 
Test for leaky discharge valves, 

204. 
Testing, for air-brake defects, 
212. 
brakes, 236. 
for leaky rotary, 215. 
and inspection ,of air-brake 

equipment, 220. 
for leaky packing rinj^s in 
pump, 213. 



Testing for leaky discharge 

valves in pump, 213. 
Time required for charging 
auxiliaries, 39. 
to detect and remedy defects, 
212. 
Train handling, 224. 
Trainmen, what they should 

know, 23. 
Trainpipe exhaust blow, cause 
of, 208. 
pressure, standard, 195. 
Triple, auxiliary and brake 
cylinder combined, 68. 
exhaust, blow at, 201. 
valve, 25. 
defective, how to locate, 

178. 
duties of, 198. 
plain, old style, illustrated, 

64. 
lap position, explained 41. 
parts, 28. 

plain, illustrated, 30. 
plain, 27. 

plain and quick-action com- 
pared, 47. 
quick-action, illustrated, 48. 
quick-actiqn, described, 46. 
principle of, 26. 
quick-action, in service posi- 
tion, illustrated, 54. 
quick-action, lap position il- 
lustrated, 56. 
quick-action, parts of, 50. 
Truck brake, locomotive, 256. 

U 
Uneven piston-travel, danger 

of, 15. 
U-spring, function of, 45. 



INDEX 



301 



W 

Warning port, function of, 137. 

Water, taking, 233. 

What trainmen should know, 

23. 
What enginemen should know, 

23. 
Whistle blowing when brakes 

are released, cause of, 217. 



Whistle signal defects, 209. 

system described, 168. 

system illustrated, 163 . 
Whistling, at triple exhaust, 
cause of. 33. 



Y, chamber in triple, 59. 



INDEX 



IKDEX OF STRAIGHT AIR BRAKE EQUIPMENT 



[Note — For Automatic Air Brake Equipment, see Special Index.] 



Action of air compressor, 274. 

Air brake, equipment, arrange- 
ment of, 283. 
handling, 271. 

Air, passage of through equip- 
ment, 283. 
pressure, standard of, 284. 

Axle-driven compressor, 274- 
275. 

Answers and questions, 286. 

Automatic and straight air 
brake, difference between, 
286. 

Automatic regulator, 278. 

B 

Brake, levers, 272-273. 
valve, positions on, 282. 



Check valve, duplex, 284. 
Cleaning compressor, 291. 
Crank shaft compressor, 276. 
Compressor, axle-driven, 274. 

axle-driven, capacity of, 277. 

defects in, how to detect, 291. 

fails to pump, 292. 

operation of, 286. 

when to clean, 291. 

working slow, cause of, 293. 



D 

Defects in compressor, how to 

detect, 291. ' 
Difference between automatic 

and straight air brakes, 286. 
Different kinds of brakes in use 

270. 
Discharge valves of compressor. 

275. 
Duplex check valve, 284. 

E 
Emergency application, 283. 
Equalizing lever, 284. 
Equipment, parts of, 272. 



Failure of compressor, 292. 

G 

Gauge, air, 280. 

Governor, compressor, 278. 

H 
Handling brake valve, 282. 

L 

Lever, equalizing, 284. 
Leaky valve, 293. 
Lubrication, 289-290. 

M 

Maintenance of equipment, 290. 



302 



INDEX 



303 



Operating valve, 279 

Oil, 289. 

Operating valve, positions on, 

282. 
Operation of compressor, 286. 

P 

Parts constituting straight air 
brake equipment, 272. 

Passage of air through equip- 
ment, 283 

Positions on brake valve, 282. 

Pressure, air, 284. 

required in emergency ap- 
plication, 289. 

required in service applica- 
tion, 288. 

Q 

Questions and answers, 286 

R 

Receiving port of compressor, 
276. 
valves of compressor, 275. 

Regulator or governor, auto- 
matic, 278 



Regulator, operation of, 287. 

pressure set at, 287. 
Releasing brake, 284. 
Running position of brake 

valve, 289. 

S 

Standard of air pressure, 284. 

Sticking valve, effect of, 292. 

Suction valves of compressor, 

275. 



Trip piston chambers, 279. 



Valves, discharge, of compres- 
sor, 275. 
receiving, of compressor, 275. 

Valve, duplex check, 284. 
operating, 279. 
sticking, effect of, 292. 

W 
What motormen and conduc- 
tors of electric cars should 
know, 269. 




The Latest, Best and Most Complete Book on Engineering and Electricity 
published. Written by practical Engineers and Electricians in a way 
that you can understand it. UP-TO-DATE 1904 EDITION. 

"^he 20th Century Hand Book 
Engineers and E^lectricians 

A COMPENDIUM 
of useful knowl- 
edge appertain- 
ing to the care and 
management of Steam 
Engines, Boilers and 
Dynamos. Thorough- 
ly practical wdth full 
instructions in regard 
to making evapora- 
tion tests on boilers. 
The adjustment of the 
slide valve, corliss 
valves, etc., fully de- 
scribed and illustrated, 
together with the ap- 
plication of the in- 
dicator and diagram 
analysis. The subject 
of hydraulics for en- 
g I n e e r s is made a 
spjecial feature, and all problems are solved in plain figvires, thus ena- 
bling the man of limited education to comprehend their meaning. 

By C. F. SWINGLE, M.E. 

Formerly Chief Engineer of the Pullman Car Works. Late Chief Engineer 
of the Illinois Car and Equipment Co., Chicago. 

ELECTRICAL DIVISION 

The electrical part of this valuable volume was written by a practical 
engineer for engineers, and is a clear and comprehensive treatise on the 
principles, construction and operation of Dynamos, Motors, Lamps, 
Storage Batteries, Indicators and Measuring Instruments, as well as an 
explanation of the principles governing the generation of alternating cur- 
rents, and a description of alternating current instruments and machin- 
ery. No better or more complete electrical part of a steam engineer's 
book was ever vsritten for the man in the engine room of an electric 
lighting plant. 

SWINGLE'S 20th CENTURY HAND BOOK 

FOR. ENGINEERS AND ELECTRICIANS 

Over 300 illustrations; handsomely bound in full leather pocket <>0 CA 
book style; size 5 x 6^ x 1 inch thick. PRICE NET . . . . v£iuU 
Sold by booksellers generally or sent postpaid to any 
address upon receipt of price. 

FREDERICK J. DRAKE & COMPANY 

Publishers of Self-Educational Books for Mechanics 

2II-2I3 East Madison Street CHICAGO. U.S.A. 



THE MOST IMPORTANT BOOK ON ELECTRICAL CONSTRUCTION 

WORK FOR ELECTRICAL WORKERS EVER PUBLISHED. 

NEW 1904 EDITION. 

MODERN WIRING 
DIAGRAMS AND DESCRIPTIONS 

A Hand Book of practical diagrams and 
information for Electrical Workers. 

By HENRY C. HORSTMANN and 
VICTOR H. TOUSLE Y 
Expert Electricians. 

This grand little volume not only tells 
you how to do it, but it shows you. 

The book contains no pictures of 
bells , batteries or other fittings ; you can 
see those anywhere. 

It contains no Fire Underwriters' 
rules; you can get those free anywhere. 
It contains no elementary considera- 
tions ; you are supposed to know what 
an ampere, a volt or a "short circuit" 
is. And it contains no historical matter. 
All of these have been omitted to 
make room for "diagrrams and de- 
scriptions" of just such a character as 
workers need. We claim to give all 
that ordinary electrical workers need 
and nothing that they do not need. 

It shows you how to wire for call and alarm bells. 

For burglar and fire alarm. 

How to run bells from dynamo current, 

How to install and manage batteries. 

How to test batteries. 

How to test circuits. 

How to wire for annunciators; for telegraph and gas lighting. 

It tells how to locate "trouble" and "ring out" circuits. 

It tells about meters and transformers. 

It contains 30 diagrams of electric lighting circuits alone. 

It explains dynamos and motors ; alternating and direct current. 

It gives ten diagrams of ground detectors alone. 

It gives "Conapensator" and storage battery installation. 

It gives simple and explicit explanation of the "Wheatstone" Bridge 
and its uses as well as volt-meter and other testing. 

It gives a new and simple wiring table covering all voltages and all 
losses or distances. 

16mo., 160 pages, 200 illustrations; full leather binding, dl*-| C/^ 
round corners, red edges. Size 4x6, pocket edition. PRICE ^p 1 .0 V^ 

Sold by booksellers generally or sent postpaid to any address 
upon receipt of price. 

FREDERICK J. DRAKE & COMPANY 

PUBLISHERS 
2II-2I3 East Madison Street CHICAGO, U.S.A. 




JUST THE BOOK FOR BEGINNERS AND ELECTRICAL WORKERS 

WHOSE OPPORTUNITIES FOR GAINING INFORMATION ON 

THE BRANCHES OF ELECTRICITY HAVE BEEN LIMITED 



ELECTRICITY 

Made Simple 

By CLARK CARYL HASKINS 

A BOOK DEVOID OF 

TECHNICALITIES 

SIMPLE. PLAIN AND 

UNDERSTANDABLE 

There are many elementary books about 
electricity upon the market but this is 
the first one presenting the matter in 
such shape that the layman may under- 
stand it, and at the same time, not writ- 
ten in a childish manner. 

FOR ENGINEERS, DYNAMO MEN, 
FIREMEN, LINEMEN, WIREMEN AND 
LEARNERS. FOR STUDY OR 
REFERENCE. 

This little work is not intended for the instruction of experts, nor as 
a guide for professors. The author has endeavored throughout the book 
to bring the matter down to the level of those whose opportunities for 
gaining information on the branches treated have been limited. 

Four chapters are devoted to Static Electricity ; three each to Chemi- 
cal Batteries and Light and Power; two each to Terrestrial Magnetism 
and Electro-Magnetism ; one each to Atmospheric Electricity ; Lightning 
Rods ; Electro - Chemistry ; Applied Electro - Magnetism ; Force, Work 
and Energy; Practical Application of Ohm's Law; also a chapter upon 
Methods of Developing Electricity, other than Chemical. 

The large number of examples that are given to illustrate the practi- 
cal application of elementary principles is gaining for it a reputation as 
a text book for schools and colleges. 

In reviewing this book an eminent electrician says of it : 

"All that 999 men out of 1000 want to know can be imparted in plain 
language and arithmetic. I therefore think that such a book as yours 
is the kind that does the greatest good to the greatest number." 

I2mo, Cloth, 233 Pages. IO8 Illustrations i/fw f\g\ 
PRICE JVet ipl*W 

For Sale by booksellers generally or sent postpaid to any 
address upon receipt of price, 

FREDERICK J. DRAKE & CO.. PubUshers 
21 1 -213 E. M&dison Street. CHICAGO. U.S.A. 




A BPOK EVERY ENGINEER AND ELECTRICIAN 
SHOULD HAVE IN HIS POCKET. A COMPLETE 
ELECTRICAL REFERENCE LIBRARY IN ITSELF 

NEW EDITION 

^/>e Handy Vest-Pocket 

ELECTRICAL 
DICTIONARY 

BY WM. L. WEBER, M.E. 




ILLUSTRATED 

CONTAINS upwards of 4,800 words, 
terms and phrases employed in the 
electrical profession, with 'their 
definitions given in the most concise, 
lucid and comprehensive manner. 

The practical business advantage 
and the educational benefit derived 
from the ability to at once understand 
the meaning of some term involving 
the description, action or functions of 
a machine or apparatus, or the physi- 
cal nature and cause of certain phe- 
nomena, cannot be overestimated, and 
will not be, by the thoughtful assidu- 
ous and ambitious electrician, because 
he knows that a thorough understand- 
ing, on the spot, and in the presence 
of any phenomena, effected by the aid 
of his little vest-pocket book of refer- 
ence, is far more valuable and lasting 
in its impression upon the mind, than 
any memorandum which he might 
make at the time, with a view to the 
future consultation of some volumin- 
ous standard textbook, and which is 
more frequently neglected or forgotten 
than done. 

The book is of convenient size for 
carrying in the vest pocket, being only 
2% inches by 5Y2 inches, and M inch 
thick; 224 pages, illustrated, and 
bound in two different styles: 

New Edition. Cloth, Red Edges, Indexed . . 25c 
New Edition. Full Leather, Gold Edges, Indexed, 50c 

Sold by booksellers generally or sent postpaid to any address upoa receM^t 
of price. 

FREDERICK J. DRAKE & COMPANY 

Publishers of Self-Educational Books for Mechanles 
aii-ai3 B. MADISON ST. CHICAGO. U.S.A. 




Easy Electrical Experiments 
and How to Make Them 

By L. P. DICKINSON 

This is the very latest and most 
valuable work on Electricity for the 
amateur or practical Electrician pub- 
lished. It gives in a simple and 
easily understood language every 
thing you should know about Gal- 
vanometers, Batteries, Magnets, In- 
duction, Coils, Motors, Voltmeters, 
Dynamos, Storage Batteries, Simple 
and Practical Telephones, Telegraph 
Instruments, Rheostat, Condensers, Electrophorous, 
Resistance, Electro Plating, Electric Toy Making, etc. 
The book is an elementary hand book of lessons, 
experiments and inventions. It is a hand book for 
beginners, though it includes, as well, examples for 
the advanced students. The author stands second to 
none in the scientific world, and this exhaustive work 
will be found an invaluable assistant to either the 
student or mechanic. 

Illustrated with hundreds of fine drawings; printed 
on a superior quality of paper. 

J2mo Cloth. Price, $1.25. 

Sent postpaid to any address upon receipt of price. 

FREDERICK J. DRAKE (Si CO. 

PUBLISHERS ' 

? 9 ^ ^ Chicago 



Fred T. Hodgson's New (1905) Books For Builders 

STEEL SQUARE 

A TREATISE OF THE PRAdTBGAL USES OF 

By FRED, T. HODGSON, Architect. 

{New and up-toodate. Published May 1st, 1903. Do not mistake this edition 
for the one published over 20 years ago. 

This is the latest practical work on 
the Steel Square and its uses pub- 
p(*»-rj^fl|i ished. It is thorough, accurate, clear 
put^jTiictS'^c I ^^^ ®^^^ ^ understood. Confounding 

fnoaCTl^cnllARLl terms and phrases have been relig- 

^eflOU^ljlJlBfl iously avoided where possible, 

^^^'''0'^^^^^jmJm and everything in the book has been 
Btl^!!-«d™IMIIIIII made so plain that a boy twelve years 
of age, possessing ordinary intelli- 
gence, can understand it from begin- 
ning to end. 

It is an exhaustive work including 
some very ingenious devices for laying 
out bevels for rafters, braces and other 
•lllilllllllllllllllllllll inclined work; also chapters on the 
Square as a calculating machine, show- 
ing how to measure Solids, Surfaces 
and Distances — very useful to builders 
^^^^ and estimators. Chapters on roofing 

'flH«»2^jre| and how to form them by the aid of 

yi'^^si^^M tlie Square. Octagon, Hexagon, Hip 
fH0''^2»S™liill'' *°^ other roofs are shown and ex- 
tlL^fimlllllllP*'^ plained, and the manner of getting 
tho rafters and jacks given. Chapters 
on heavy timber f ramin g , phowin g how 
the Square is used for laying out Mor- 
tises, Tenons, Shoulders, Inclined 
Work, Angle Corners and similai 
work. The work also contains a large number of diagrams, showing how 
the Square may be used in finding Bevels, Angles , Stair Treads and bevel 
cuts f(jr Hip, valley. Jack and other Rafters, besides methods for laying 
out Stair Strings, Stair Carriages and Timber Structures generally. Also 
contains 25 beautiful halftone illustrations of the perspective and floor plans 
of 25 medium priced houses. 

The work abounds with hundreds of fine illustrations and explana* 
tory diagrams which will prove a perfect mine of instruction for the 
mechanic, young or old. 

Two large volumes, 560 pages, nearly 500 illustrations, printed on a 
superior quality of paper from new large type. 

Price, 2 Vols., cloth binding $2.00 

Price, 2 Vols., hall=leather binding 3.00 

5ingle Volumes, Part I, cloth 1.00 

•• Part I, half- leather 1.50 

•• Partil.cloth l.Otf 

•t .0 Part 11, one half-leather t,Si 

SEND FOR COMPLETE ILLUSTRATED CATALOGUE FREE 

FREDERICK J. DRAKE ®. CO. 

PUBLISHERS OF SELF-EDUCATrONAL BOOKS 
211 E. MADISON STILEET ^ V» CHICAGO 




Modern Carpentry 

A PiyACTICAL MANUAL 

FOR CARPENTERS AND WOOD WORKERS GENERALLY 

y ITIED T. Hodgson, Architect, Editor of the National Builder, Practical 
Carpentry, Steel Square and Its Uses, etc., etc. 

A NEW, complete guide, containing hundreds of quicfc 
*^ methods for performing work in carpentry, joining and 

general wood-work. Like all of Mr. Hodgson's works, it is 

written in a simple, every-day style, and 

does not bewilder the working-man 

with long mathematical formulas or 

abstract theories. The illustrations, of 

which there are many, are explanatory, 

so that any one who can read plain 

English will be able to understand them 

easily and to follow the work m hand 

without difficulty. 

The book contains methods of laying 
roofs, rafters, stairs, floors, hoppers, 
bevels, joining mouldings, mitering, 
coping, plain hand-railing, circular 
work, splayed work, and many other 
things the carpenter wants to know to help 
him in his every day vocation. It is the 
mo^ complete and very latest work published, being thorough 
practical and reliable. One which no carpenter can afford .o 
be without. 

The work is printed from new, large type plates on a superior quaint 
of cream wove paper, durably bound in English cloth. 



HODERN CARPENTRY 
fMD.I HODGSON 




Prioe 



$(.00 



FREDERICK J. DRAKE & CO. 

211-213 E. Madison St., Chicago. 



